All About
Servicing
OVER THE RANGE
MICROWAVE OVENS
With Standard And Electronic Controls
™
Electrolux Major Appliances; North America
250 Bobby Jones Expwy
Augusta, GA 30907
Publication #5995543534
Part # 316439279
June 2009
Section 1 Basic Information
Safe Servicing Practices
Avoid personal injury and/or property damage by observing important Safe Servicing Practices.
Following are some limited examples of safe practices:
1.
DO NOT attempt a product repair if you have any doubts as to your ability to complete the repair in a safe and
satisfactory manner.
2.
Always Use The Correct Replacement Parts as indicated in the parts documentation. Substitutions may defeat
compliance with Safety Standards Set For Home Appliances. Do not exceed maximum recommended wattage on
light bulb replacements. Doing so could blow fuses and/or damage transformers.
3.
Before servicing or moving an appliance:
•
Remove power cord from the electrical outlet, trip circuit breaker to the OFF position, or remove fuse.
4. Never interfere with the proper operation of any safety device.
5.
Use ONLY REPLACEMENT PARTS CATALOGED FOR THIS APPLIANCE. Substitutions may defeat compliance with
Safety Standards Set For Home Appliances.
6.
GROUNDING: The standard color coding for safety ground wires is GREEN, or GREEN with YELLOW STRIPES.
Ground leads are not to be used as current carrying conductors. It is EXTREMELY important that the service
technician reestablish all safety grounds prior to completion of service. Failure to do so will create a hazard.
7. Prior to returning the product to service, ensure that:
•
All electrical connections are correct and secure.
•
All electrical leads are properly dressed and secured away from sharp edges, high-temperature components,
and moving parts.
•
All non-insulated electrical terminals, connectors, heaters, etc. are adequately spaced away from all metal
parts and panels.
•
All safety grounds (both internal and external) are correctly and securely connected.
•
All panels are properly and securely reassembled.
© 2009 Electrolux Home Products, Inc.
1-1
Section 1 Basic Information
This Manual has been prepared to provide Electrolux Service Personnel with Operation and Service Information for
Electrolux Microwave Ovens FGMV173KB, FGMV173KQ, FGMV173KW, FGMV174KM, FGMV174KF, DGMV174KF and
DGMV174KMA.
Table of Contents
Section 1 Basic Information
Safe Servicing Practices ........................................ 1-1
Table of Contents ................................................. 1-2
Warnings and Safety Information .......................... 1-3
Precautions To Be Observed Before And During
Servicing To Avoid Possible Exposure To
Excessive Microwave Energy ................................. 1-4
Before Servicing ................................................... 1-4
Danger High Voltage ............................................ 1-4
Before Servicing ................................................... 1-5
When Testing Is Completed .................................. 1-5
Microwave Measurement Procedure USA ................ 1-6
Microwave Measurement Procedure Canada ........... 1-7
Product Specification ............................................ 1-8
Grounding Instructions ......................................... 1-9
Electrical Requirements ........................................ 1-9
Oven Diagram ...................................................... 1-10
Section 2 Operation
Operating Sequence Description ............................
Off Condition ....................................................
Cooking Condition .............................................
Ventilation Methods Hot Air Exhaust ......................
Power Level P-0 To P-90 Cooking ..........................
Sensor Cooking Condition .....................................
Cooking Sequence ................................................
Oven Schematic-Off Condition ...............................
Oven Schematic-Cooking Condition........................
Touch Control Panel Assembly Outline ...................
Key Unit ...........................................................
Control Unit ......................................................
Component Descriptions .......................................
Door Open Mechanism .........................................
Door Sensing And Secondary Interlock Switch ........
Monitor Switch .....................................................
Thermal Cut-Out (Cavity) ......................................
Thermal Cut-Out (Hood) .......................................
Turntable Motor ...................................................
Cooling Fan Motor ................................................
Hood Fan Motor ...................................................
Hood Lamp ..........................................................
Humidity Sensor Circuit.........................................
1-2
2-1
2-1
2-1
2-2
2-2
2-3
2-3
2-4
2-4
2-5
2-5
2-5
2-5
2-5
2-5
2-6
2-6
2-6
2-6
2-6
2-6
2-6
2-7
Section 3 Troubleshooting and Testing
Warnings and Cautions .........................................
Troubleshooting Guide Chart .................................
Test Procedures ...................................................
Section 4 Component Teardown
Warnings and Cautions .........................................
Hood Exhaust Louver Removal ..............................
Removal Of Oven From Wall .................................
Outer Case Removal .............................................
Power Transformer Removal .................................
Hood Fan Motor, Hood Duct, Oven Lamp
Socket And AH Sensor Removal.............................
Magnetron Removal .............................................
High Voltage Rectifi er And High Voltage
Capacitor Removal ...............................................
Hood Fan Thermal Cut-Out Removal......................
Thermal Cut-Out (Cavity) Removal ........................
Cooling Fan Motor Removal ..................................
Turntable Motor And Food Lamp Sockets ...............
Stirrer Motor Removal...........................................
Stirrer Cover And Stirrer Fan Installation ................
Positive Lock® Connector (No-Case Type)
Removal ..............................................................
Servicing The Touch Control Panel .......................
Control Panel Assembly And Control Unit Removal ..
Graphic Sheet And Membrane Switch Replacement .
Door Sensing Switch, Secondary Interlock
Switch And Monitor Switch Removal ......................
Door Sensing Switch, Secondary Interlock
Switch, And Monitor Switch Adjustment .................
Door Replacement ................................................
Door Disassembly.................................................
3-1
3-2
3-3
4-1
4-2
4-2
4-2
4-3
4-3
4-4
4-4
4-5
4-5
4-6
4-6
4-7
4-7
4-7
4-8
4-10
4-10
4-11
4-11
4-12
4-13
Section 5 Wire Diagrams
Wiring Schematic Oven OFF Condition ...................
Wiring Diagram ....................................................
Control Wiring Schematic ......................................
Printed Wiring Board ............................................
5-1
5-2
5-3
5-4
Section 6 Parts List
Control Panel Parts ...............................................
Oven And Cabinet Parts Exploded View ..................
Oven And Cabinet Parts List ..................................
Door Parts for FGMV185KB/W ...............................
Packing and Accessories Exploded View .................
6-1
6-2
6-3
6-5
6-6
Section 1 Basic Information
WARNING
Certain initial parts are intentionally not grounded and present a risk of electrical shock only during
servicing. Service personnel - do not contact the following parts while the appliance is energized:
Inverter unit, that includes high voltage capacitor, high voltage power transformer, high voltage
rectifier, heat sink, etc., magnetron, high voltage harness etc.;
If provided, fan assembly, cooling fan motor.
All the parts marked “*” on parts list are used at voltages more than 250v.
Removal of the outer wrapper gives access to voltage above 250v.
All the parts marked “ä” on parts list may cause undue microwave exposure, by themselves, or when
they are damaged, loosened or removed.
WARNING
This service manual is intended for use by persons having electrical and mechanical training and a
level of knowledge of these subjects generally considered acceptable in the appliance repair trade.
Electrolux home products cannot be responsible, nor assume any liability, for injury or damage of
any kind arising from the use of this manual.
WARNING
Never operate the oven until the following points are ensured.
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is no other visible damage with the oven.
Servicing and repair work must be carried out only by trained service personnel.
1-3
Section 1 Basic Information
Precautions To Be Observed Before And During Servicing To Avoid Possible Exposure To
Excessive Microwave Energy
1. Do not operate or allow the oven to be operated with the door open.
2. Make the following safety checks on all ovens to be serviced before activating the magnetron or other micro
wave source, and make repairs as necessary: (1) interlock operation, (2) proper door closing, (3) seal and
sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and latches,
(5) evidence of dropping or abuse.
3. Before turning on microwave power for any service test or inspection within the microwave generating
compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment, integrity,
and connections.
4. Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation and
transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the
oven is released to the owner.
5. A microwave leakage check to verify compliance with the Federal Performance Standard should be performed on
each oven prior to release to the owner.
Before Servicing
Before servicing an operative unit, perform a microwave emission check as per the Microwave Measurement
Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact ELECTROLUX HOME PRODUCTS, INC.
immediately.
If the unit operates with the door open, service person should:
1. Tell the user not to operate the oven.
2. Contact Electrolux HOME PRODUCTS, INC. and Food and Drug Administration’s Center for Devices and
Radiological Health immediately.
Service personnel should inform ELECTROLUX HOME PRODUCTS, INC. of any certified unit found with emissions in
excess of 4mW/cm2. The owner of the unit should be instructed not to use the unit until the oven has been brought
into compliance.
Danger High Voltage
Do not energize a microwave oven with the outer case cabinet removed, because a microwave oven generates high
voltage in the circuit.
If you intend to operate the oven employing the high frequency switching power converter circuit, you should take
special precautions to avoid an electrical shock hazard.
The high voltage transformer, high voltage capacitor and high voltage diode have energized high voltage potential
of approximately 8KV.
The aluminium heat sink is connected to the switching power transistor collector pole, and has an energized high
voltage potential of approximately 650V peak.
DO NOT ACCESS THE HIGH VOLTAGE TRANSFORMER, HIGH VOLTAGE CAPACITOR, HIGH VOLTAGE DIODE AND HEAT SINK WHEN THE POWER SUPPLY IS CONNECTED TO AN ELECTRICAL OUTLET.
1-4
Section 1 Basic Information
WARNING
Microwave ovens contain circuitry capable of producing
very high voltage and current. contact with THE
following parts may result in a severe, possibly fatal,
electrical shock.
Don't Touch!
Danger High
Voltage
Inverter unit, that includes High Voltage Capacitor,
High Voltage Power Transformer, High Voltage Rectifier,
Heat sink etc., and Magnetron, High Voltage Harness etc..
Read the Service Manual carefully and follow all
instructions.
Before Servicing
When Testing Is Completed
1. Disconnect the power supply cord, and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
1.
2.
3.
NOTE
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
Disconnect the power supply cord, and then remove
outer case.
Open the door and block it open.
Discharge high voltage capacitor.
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
Whenever troubleshooting is performed, the power
supply must be disconnected. It may, in some cases, be
necessary to connect the power supply after the outer
case has been removed, in this event:
4.
5.
6.
1. Disconnect the oven power supply cord and then
remove the outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect leads to the primary of the inverter unit.
5. Ensure that these leads remain isolated from other
components and oven chassis by using insulation
tape.
6. After that procedure, reconnect the power supply
cord.
7.
Reconnect leads to the primary of the inverter unit.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer
case is installed.
Run the oven and check all functions.
After repairing
1. Reconnect all leads removed from components
during testing.
2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer
case is installed.
4. Run the oven and check all functions. Microwave
ovens should not be run empty. To test for the
presence of microwave energy within a cavity,
place a cup of cold water on the oven turntable,
close the door and set the power to HIGH and then
set the microwave timer for two (2) minutes. When
the two minutes has elapsed (timer at zero) carefully check that the water is now hot. If the water
remains cold carry out Before Servicing procedure
and re-examine the connections to the component
being tested.
1-5
Section 1 Basic Information
Microwave Measurement Procedure (USA)
A. Requirements:
1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a
microwave oven should not exceed 1 mW/cm2 at any point 5 cm or more from the external surface of the
oven, measured prior to acquisition by a purchaser, and thereafter (through the useful life of the oven),
5 mW/cm2 at any point 5 cm or more from the external surface of the oven.
2) Safety interlock switches: Primary interlock switch shall prevent microwave radiation emission in excess of the
requirement as above mentioned, secondary interlock switch shall prevent microwave radiation emission in
excess of 5 mW/cm2 at any point 5 cm or more from the external surface of the oven.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance
standard for microwave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20°±5°C (68°F) in the center of the oven cavity.
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm
(3-1/2 in.) and made of an electrically nonconductive material such as glass or plastic. The placing of this
standard load in the oven is important not only to protect the oven, but also to insure that any leakage is
measured accurately.
4) Set the cooking control on Full Power Cooking Mode.
5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is
completed, replace it with 275 ml of cool water.
C. Leakage test:
Closed-door leakage test (microwave measurement)
1) Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and
the body of the oven.
2) Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum
indication on the meter.
3) Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity
of the metal has been breached (eg., around the switches, indicator, and vents). While testing for leakage
around the door pull the door away from the front of the oven as far as is permitted by the closed latch
assembly.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than
4 mW/cm2, and that the primary interlock switch and secondary interlock switch do turn the oven OFF before
any door movement.
NOTE: After servicing, record data on service invoice and microwave leakage report.
1-6
Section 1 Basic Information
Microwave Measurement Procedure (Canada)
After adjustment of the door switches are completed individually or collectively, switch test and microwave leakage test
must be performed with survey instrument and test result must be confirmed to meet the requirement of the
performance standard for microwave ovens as under mentioned.
A. Requirements:
Every microwave oven shall function in such a manner that when the oven is fully assembled and operating with
its service controls and user controls adjusted to yield the maximum output, the leakage radiation, at all points at
least 5 cm. from the external surface of the oven, does not exceed:
1) 1.0 mW/cm2 with the test load of 275 ± 15 ml of water at an initial temperature 20 ±5°C.
2) 5.0 mW/cm2 when the outer enclosure is removed with a test load of 275 ± 15 ml of water at an initial
temperature 20±5°C.
3) 5.0 mW/cm2 without a test load.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Survey instruments that comply with the requirement for instrumentation as prescribed by CSA and NHW
performance standard for microwave ovens must be used for testing recommended instruments are, NARDA
8100 and NARDA 8200.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20°±5°C (68°F) in the center of oven cavity.
The water container shall be a low form of a 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm
(3-1/2 in.) and made of an electrically nonconductive material such as glass or plastic. The placing of this
standard load in the oven is important not only to protect the oven, but also to insure that any leakage
is measured accurately.
4) Set the cooking control on Full Power Cooking Mode.
5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is
completed, replace it with 275 ml of cool water.
C. Leakage test with enclosure installed:
1) Grasp probe of survey instrument and hold it perpendicular to gap between door and the body of the oven.
2) Move the probe slowly, not faster than 2.5 cm/sec. along the gap, watching for maximum indication on meter.
3) Check for leakage at the door screen, sheet metal seams and other accessible positions where continuity
of the metal has been breached (eg., around the switches, indicator, and vents). While testing for leakage
around door, pull door away from the front of the oven as far as is permitted by the closed latch assembly.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater
than 4 mW/cm2, and that the primary interlock switch and secondary interlock switch do turn the oven
OFF before any door movement.
D. Leakage test without enclosure:
1) Remove the enclosure (cabinet).
2) Grasp the probe of the survey instrument and hold it perpendicular to all mechanical and electric parts of the
oven that is accessible to the user of the oven including, but not limited to, the waveguide, cavity seams,
magnetron gap between the door and the body of the oven.
3) Move probe slowly, not faster than 2.5 cm/sec. along the gap, watching for the maximum indication on meter.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is under 5 mW/cm2.
CAUTION: Special attention should be given to avoid electrical shock because HIGH VOLTAGE is
generated during this test.
E. No Load test
1) Operate the oven without a load and measure the leakage by the same method as the above test procedure
“ Leakage test with enclosure installed”
2) Make sure that the highest leakage should not exceed 5 mW/cm2.
NOTE: After servicing, record data on service invoice and microwave leakage report.
1-7
Section 1 Basic Information
Product Specification
Item
Description
Power Requirements
(USA)120 Volts / 14 Amperes
60 Hertz
Single phase, 3 wire grounded
Power Output
1000 watts (IEC 705 Test Procedure)
Operating frequency of 2450MHz
Case Dimensions (excluding handle)
Width 29-15/16”
Cooking Cavity Dimensions
(1.7 Cubic Feet )
Width 21”
Height 8-7/8”
Depth 14-7/16”
Hood Lamp
20 Watt x 2 incandescent light bulb
Oven Cavity Light
20W x 1 incandescent light bulb
Weight
Approx. 54. lbs. (net), 64 lbs. (gross)
Hood fan
Approx. 300 C.F.M. High Mode
Control Complement
Touch Control System
Clock ( 1:00 - 12:59 )
Timer (0 - 99 min. 99 seconds)
Microwave Power for Variable Cooking
Repetition Rate;
P-HI Full power throughout the cooking time
P-90 approx. 90% of Full Power
P-80 approx. 80% of Full Power
P-70 approx. 70% of Full Power
P-60 approx. 60% of Full Power
P-50 approx. 50% of Full Power
P-40 approx. 40% of Full Power
P-30 approx. 30% of Full Power
P-20 approx. 20% of Full Power
P-10 approx. 10% of Full Power
P-0 No power throughout the cooking time
Height 17-1/16”
Depth 17-15/16”
Timer on-off pad, Turntable on-off pad, User Pref pad, Sensor Cook pad,
Sensor Reheat pad, Auto Cook pad, Chicken nuggets pad, Snacks Menu
pad, Auto Defrost pad, Popcorn pad, Baked Potato pad, Vegetables pad,
Number pads, Quick start pads, START/Enter/+30sec pad, STOP/Clear pad
Power level pad, Light Hi/Lo/Off pad, Vent Hi/Lo/Off pad.
Safety Standard
1-8
UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J
Canadian Standards Association
Health CANADA, Industry Canada
Section 1 Basic Information
Grounding Instructions
This oven is equipped with a three prong grounding
plug. It must be plugged into a wall receptacle that is
properly installed and grounded in accordance with the
National Electrical Code, local codes and ordinances.
In the event of an electrical short circuit, grounding
reduces the risk of electric shock by providing an escape
wire for the electric current.
WARNING
Improper use of the grounding plug can result in
a risk of electric shock.
3-Pronged Plug
Grounded
Receptacle Box
Electrical Requirements
The oven is equipped with a 3-prong grounding plug.
DO NOT UNDER ANY CIRCUMSTANCES CUT OR
REMOVE THE GROUNDING PIN FROM THE PLUG.
The power supply cord and plug must be connected to a
separate 120 Volt AC, 60 Hz, 15 Amp. or more dedicated
line, using a grounded receptacle. When installing this
appliance, observe all applicable codes and ordinances.
A short power-supply cord is provided to reduce risks of
becoming entangled in or tripping over a longer cord.
Where a two-pronged wall-receptacle is encountered,
it is the personal responsibility and obligation of the
customer to contact a qualified electrician and have it
replaced with a properly grounded three-pronged wall
receptacle or have a grounding adapter properly
grounded and polarized.
Grounding Pin
3-Pronged Receptacle
If an extension cord must be used, it should be a 3-wire,
15 amp. or more cord. Do not drape over a countertop
or table where it can be pulled on by children or tripped
over accidentally.
1-9
Section 1 Basic Information
Oven Diagram
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Microwave oven door with see-through window.
Door hinges.
Waveguide cover. DO NOT REMOVE.
Turntable motor shaft.
Microwave oven lamp. It will light when oven is
operating or door is open.
Rack holders.
Safety door latches. The microwave oven will not
operate unless the door is securely closed.
Handle.
Light hi/lo/off pad. Press the light hi/lo/off pad once
for high, twice for low and three times to turn off
the light.
Vent hi/lo/off pad. Press the vent hi/lo/off pad once
for high speed, twice for low speed and three times
to turn off the fun.
Front View
11.
12.
13.
14.
15.
16.
17.
18.
19.
Auto-Touch control panel.
Time display: Digital display, 99 min., 99 seconds.
Ventilation openings.
Removable turntable. The turntable will rotate
clockwise or counterclockwise. Only remove for
cleaning.
Removable turntable support. First, carefully place
the turntable support in the motor shaft in the
center of the microwave oven floor. Then, place the
turntable on the turntable support securely.
Rack for 2-level cooking/ reheating
Light cover.
Grease filters.
Menu label.
13 19
12
4
2
7
8
1
3
11
6
6
5
9
7
10
14
16
15
Bottom View
18
1-10
17
(Front of microwave oven)
(Rear of microwave oven)
Section 2 Operation
Operating Sequence Description
The following is a description of component functions
during oven operation.
OFF CONDITION
Closing the door activates the door sensing switch and
secondary interlock switch. (In this condition, the
monitor switch contacts are opened.) When oven is
plugged in, 120 volts AC is supplied to the control unit.
(Figure 2-1).
1. The display will show “ENJOY YOUR OVEN PRESS
CLEAR”. To set any program or set the clock, you
must first touch the STOP/CLEAR button. The display will clear, and “ : “ appears.
COOKING CONDITION
Program desired cooking time touching the NUMBER
pads. When the START pad is touched, the following
operations occur:
1. The contacts of relays are closed and components
connected to the relays are turned on as follows.
(For details, refer to Figure 2-2)
RELAY CONNECTED COMPONENTS
RY1
Oven Lamp / Fan motor / Stirrer motor
RY2
Power Transformer
RY7
Turntable Motor
6. When the door is opened during a cook cycle,
monitor switch, door sensing switch, primary
interlock switch, and secondary interlock relay are
activated with the following results. The circuits to
the stirrer motor, the cooling fan motor, the
turntable motor, and the high voltage components
are de-energized, and the digital read-out displays
the time still remaining in the cook cycle when the
door was opened.
7. The monitor switch is electrically monitoring the
operation of the primary interlock switch, and door
sensing switch is mechanically associated with
the door so that it will function in the following
sequence.
(1) When the door opens from a closed position,
the secondary interlock relay, door sensing
switch, and primary interlock switch open their
contacts, and then the monitor switch contacts
close.
(2) When the door is closed from the open position,
the monitor switch contacts open first. Then the
contacts of the primary interlock switch and
door sensing switch close. And contacts of the
relay (RY1) open.
If the primary interlock switch and secondary interlock
relay (RY2) fail with the contacts closed when the door
is opened, the closing of the monitor switch contacts will
form a short circuit through the monitor fuse, primary interlock switch, relay (RY1) and secondary interlock relay
(RY2), causing the monitor fuse to blow.
2. 120 volts AC is supplied to the primary winding of
the power transformer and is converted to about
3.3 volts AC output on the filament winding, and
approximately 2000 volts AC on the high voltage
winding.
3. The filament winding voltage heats the magnetron
filament and the H.V. winding voltage is sent to a
voltage doubler circuit.
4. The microwave energy produced by the magnetron
is channeled through the waveguide into the cavity
feedbox, and then into the cavity where the food
is placed to be cooked.
5. Upon completion of the cooking time, the power
transformer, oven lamp, etc. are turned off, and the
generation of microwave energy is stopped. The
oven will revert to the OFF condition.
2-1
Section 2 Operation
VENTILATION METHODS HOT AIR EXHAUST
POWER LEVEL P-0 TO P-90 COOKING
1. Vertical Venting
When Variable Cooking Power is programmed, the
120 volts A.C. is supplied to the power transformer
intermittently through the contacts of relay (RY2) which
is operated by the control unit within an interval second
time base. Microwave power operation is as follows:
For this venting method, hot air rising from the
conventional range below is drawn in by the hood fan
motor through the grease filters at the right and left
sides of the base cover, up through the right and left
sides of the oven cavity, then discharged vertically at rear
center top of the oven, into the customer’s vent system.
To Duct
To Duct
Hood Fan
Motor
Hood
Intake
Duct R
Grease
Filter
2. Horizontal Venting
The air handing is the same as Vertical Venting except
that final air discharge is directed horizontally out from
the top rear of oven into the customer’s vent system.
Hood Fan
Motor
To Duct
Hood
Intake
Duct R
Grease
Filter
3. Re-circulation (Inside venting)
The air handing is the same as VERTICAL VENTING
except that the final air discharge is directed horizontally
through the upper front of the oven into the kitchen. In
this case, the accessory charcoal Filter RK-240 must be
provided to filter the air before it leaves the oven.
Hood Fan
Motor
Hood Exhaust
Louver
Hood
Intake
Duct R
2-2
Charcoal
Filter
Vari-Mode
ON TIME
OFF TIME
Power
Power
Power
Power
Power
Power
Power
Power
Power
Power
Power
32 sec.
30 sec.
26 sec.
24 sec.
22 sec.
18 sec.
16 sec.
12 sec.
8 sec.
6 sec.
0 sec.
0 sec.
2 sec.
6 sec.
8 sec.
10 sec.
14 sec.
16 sec.
20 sec.
24 sec.
26 sec.
32 sec.
10 (High) (100% Power)
9 (P-90) (Approx. 90%)
8 (P-80) (Approx. 80%)
7 (P-70) (Approx. 70%)
6 (P-60) (Approx. 60%)
5 (P-50) (Approx. 50%)
4 (P-40) (Approx. 40%)
3 (P-30) (Approx. 30%)
2 (P-20) (Approx. 20%)
1 (P-10) (Approx. 10%)
0 (P-0) (0% power)
NOTE
The ON/OFF time ratio does not correspond with
the percentage of microwave power, because
approximately 2 seconds are needed for heating of
the magnetron filament.
Section 2 Operation
SENSOR COOKING CONDITION
COOKING SEQUENCE
Using the SENSOR function, the foods are cooked
without figuring time, power level or quantity. When the
oven senses enough steam from the food, it relays the
information to its microprocessor which will calculate the
remaining cooking time and power level needed for best
results.
1. Operate the oven in sensor cooking mode by
referring to the operation manual.
When food is cooked, water vapor is developed. The
sensor “senses” the vapor and its resistance increases
gradually. When the resistance reaches the value set
according to the menu, supplementary cooking is started.
The time of supplementary cooking is determined by
experiments with each food category and inputted into
the LSI.
An example of how the sensor works:
(BAKED POTATOES)
1.
Potatoes at room temperature. Vapor is emitted
very slowly.
NOTE
The oven should not be operated on Sensor Cooking
immediately after plugging in the unit. Wait two
minutes before cooking on Sensor Cooking.
2. The coil of shut-off relays (RY1) are energized, the
oven lamp, turntable motor and cooling fan motor
are turned on, but the power transformer is not
turned on.
3. After about 32 seconds, the relay (RY2) is energized.
The power transformer is turned on, microwave
energy is produced and first stage is started.
The 32 seconds is the cooling time required to
remove any vapor from the oven cavity and sensor.
NOTE
During this first stage, do not open the door or touch
Clear/Off pad.
2. Heat Potatoes. Moisture and humidity is emitted
rapidly. You can smell the aroma as it cooks.
MIC
ROW
AVE
3. Sensor detects moisture and humidity and
calculates cooking time and variable power.
AH SENSOR
4. When the sensor detects the vapor emitted from
the food, the display switches over to the remaining
cooking time and the timer counts down to zero.
At this time, the door may be opened to stir food,
turn it or season, etc.
5. When the timer reaches zero, an audible signal
sounds. The shutoff relay and cook relay are
generalized and the power transformer, oven lamp,
etc. are turned off.
6. Opening the door or touching the STOP CLEAR pad,
the time of day will reappear on the display and the
oven will revert to an OFF condition.
MIC
ROW
AVE
2-3
Section 2 Operation
NOTE: "
SCHEMATIC
" indicates components with potential above 250V
NOTE S :
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. CLOCK APPEARS ON DISPLAY
1. C ircuits subject to change without notice.
2. Terminal with projecttion or opposite blue mark on lamp socket must
be connected to neutral wire.
3. Only certain models use the absolute humidity sensor.
4. P ower Transformer (Start Lead) terminal must be connected to hot
wire (R E D)
MG .
TE MP. FUS E
BLK
YLW
YLW
BLK
L
P OWE R
TR ANS FOR ME R
GRN
E2
LVT
RY3
LINE BYPAS S C APAC ITOR
0.0033uF 250V
BLK
WHT
C5
2
TUR NTABLE
MOTOR
R E LAY
S TOP
S WITC H
YLW
HOOD FAN
THE R MAL
C UT OUT
6
B3
RY5
E1
RY2
RY6
HOOD
C APAC ITOR
3
F3
S E C ONDR Y
INTE R LOC K
R E LAYA
C OM
MONITOR
S WITC H
BLK
N.C .
High
Low
N.C .
HIG H
VOLTAG E
C APAC ITOR
0.94uF
F2
1F
C OM.
HUMIDITY
S E NS OR
G ND
HIG H
VOLTAG E
R E C TIFIE R
WHT
WHT
WHT
G RY
WHT
WHT
N.O.
WHT
OR G
PPL
RED
C3
A7
A9
A3
YLW
A1
HOOD
LAMP
HOOD
MOTOR
HL
HL
N
5
4
WHT
G RY
NOIS E FILTE R
G RY
BLU
G RY
WHT
1
BLU
WHT
G ND
LINE BYPAS S C APAC ITOR
0.0033uF 250V
120V AC
60Hz
R E S ISTOR 470 k ohm 1/2W
GRN
NOIS E S UP R E S S ION C OIL
LINE C R OS S C APAC ITOR 1.0 uF 275V
BLK
FUS E 20A
C1
MAG NE TR ON
RED
BLK
RY1
RY4
B1
C OM
OVE N
LAMP
R E LAY
GRN GRN
GRN
A5
BLK
RY7
N.O.
C ONTR OL UNIT
RED
BLK
RED
FANM
OTOR
S TIR R E R
MOTOR
BLK
YLW
OVE N
LAMP
BLU
G RY
OVE N THE R MAL
C UT OUT
WHT
WHT
TUR NTABLE
MOTOR
G R AY
WHITE
BLUE
GREEN
YE LLOW
WHT
BLU
:
:
:
:
:
RED
GRY
WHT
BLU
GRN
YLW
BLAC K
BR OWN
OR ANG E
P INK
P UR P LE
RED
RED
:
:
:
:
:
:
RED
BLK
LE AD WIR E C OLOR C ODE
BLK
BR N
OR G
P NK
PPL
RED
N.O
P R I MAR Y
INTE R LOC K
S WITC H
BLK
BLU
BLU
C OM
YLW
YLW
RED
YLW
RED
Figure 2-1. Oven Off Condition
MG .
TE MP. FUS E
YLW
YLW
FANM
OTOR
YLW
YLW
BLK
N
NOIS E FILTE R
2-4
WHT
BLK
6
P OWE R
TR ANS FOR ME R
S TOP
S WITC H
3
B3
RY5
E1
N.C .
RY2
RY6
HOOD
C APAC ITOR
S E C ONDR Y
INTE R LOC K
RE LAYA
F3
C OM.
N.C .
HUMIDITY
S E NS OR
WHT
WHT
N.O.
G RY
WHT
WHT
C3
A7
OR G
A9
PPL
YLW
RED
A3
HIG H
VOLTAG E
C APAC ITOR
0.94uF
F2
1F
A1
C OM
MONITOR
S WITC H
BLK
High
Low
MAG NE TR ON
GRN
E2
LVT
RY3
LINE BYPAS S C APAC ITOR
0.0033uF 250V
C5
2
TUR NTABLE
MOTOR
R E LAY
YLW
HOOD FAN
THE R MAL
C UT OUT
G ND
HIG H
VOLTAG E
R E C TIFIE R
HOOD
LAMP
HL
G RY
WHT
HL
WHT
G RY
1
4
G RY
BLU
HOOD
MOTOR
BLU
WHT
G ND
NOIS E S UP R E S S ION C OIL
R E S IS TOR 470 k ohm 1/2W
120V AC
60Hz
LINE C R OS S C APAC ITOR 1.0 uF 275V
GRN
LINE BYPAS S C APAC ITOR
0.0033uF 250V
FUS E 20A
BLK
BLK
RED
L
C1
WHT
WHT
RED
BLK
RY1
RY4
B1
C OM
OVE N
LAMP
R E LAY
GRN GRN
GRN
A5
BLK
RY7
N.O.
C ONTR OL UNIT
RED
BLK
YLW
RED
BLK
S TIR R E R
MOTOR
WHT
RED
RED
OVE N
LAMP
BLU
G RY
TUR NTABLE
MOTOR
OVE N THE R MAL
C UT OUT
N.O
P R IMAR Y
INTE R LOC K
S WITC H
BLK
BLU
BLU
C OM
YLW
BLK
RED
WHT
WHT
RED
5
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. COOKING TIME PROGRAMMED.
3. VARIABLE COOKING CONTROL "100%".
4. START PAD TOUCHED.
Figure 2-2. Oven ON (Cooking) Condition
Section 2 Operation
Touch Control Panel Assembly Outline
The touch control section consists of the following units.
(1) Key unit
(2) Control Unit: The Control unit consists of LSI Unit and
Power Unit.
The principal functions of these units and the signals
communicated among them are explained below.
7. Relay Circuit
To drive the magnetron, fan motor, turntable motor,
hood motor, and light the oven lamp and hood lamp.
8. Indicator Circuit
This circuit consists of 25 segments and 4 common
electrodes using a Light Crystal Display.
9. Back Light Circuit
A circuit to drive the back light (Light emitting diodes
LD1-LD5).
KEY UNIT
The key unit is composed of a matrix, signals generated
in the LSI are sent to the key unit through P40 - P47.
When a key pad is touched, a signal is completed
through the key unit and passed back to the LSI through
P20, P21, P22, P00 and P01 to perform the function that
was requested.
Component Descriptions
DOOR OPEN MECHANISM
The door is opened by pulling the door handle, refer to
the Figure 2-3.
Latch Heads
CONTROL UNIT
Control unit consists of LSI, power source circuit,
synchronizing signal circuit, reset circuit, buzzer circuit,
relay circuit indicator circuit and back light circuit.
1. (LSI)
This LSI controls the key strobe signal, relay driving
signal for oven function and indicator signal.
2. Power Source Circuit
This circuit generates voltages necessary for the
control unit from the AC line voltage. In addition,
the synchronizing signal is available in order to
compose a basic standard time in the clock circuit.
Symbol
Voltage
Application
VC
-5.0V
LSI(IC1)
3. Synchronizing Signal Circuit
The power source synchronizing signal is available in
order to compose a basic standard time in the clock
circuit. It incorporates a very small error because it
works on commercial frequency.
4. Reset Circuit
This circuit generates a signal which resets the LSI
(IC1) to the initial state when power is supplied.
5. Buzzer Circuit
The buzzer is responds to signals from the LSI to
emit audible sounds (key touch sound and
completion sound).
6. Door Sensing Switch
A switch to inform the LSI if the door is open or
closed.
Latch Hook
Door
Primary Interlock
Switch
Monitor Switch
Door Sensing Switch
Figure 2-3. Door Open Mechanism
DOOR SENSING AND PRIMARY INTERLOCK
SWITCH
The primary interlock switch is mounted in the upper
position of the latch hook, and the door sensing switch in
the primary interlock system is mounted in the lower
position of the latch hook. The switches are activated by
the latch heads on the door. When the door is opened,
the switches interrupt the circuit to all components.
A cook cycle cannot take place until the door is firmly
closed, thereby activating both interlock switches. The
primary interlock system consists of the door sensing
switch and secondary interlock relay located on the
control circuit board.
2-5
Section 2 Operation
MONITOR SWITCH
THERMAL CUT-OUT (HOOD )
The monitor switch is activated (the contacts opened)
by the latch head on the door while the door is closed.
The switch is intended to render the oven inoperative, by
means of blowing the monitor fuse when the contacts of
the primary interlock relay (RY2) and secondary interlock
switch fail to open when the door is opened.
This thermal cut-out located on the right base plate. It
is designed to automatically turn on the hood fan motor
whenever the hot air rising from the conventional range
below causes the temperature at the thermal cut-out to
rise to 158°F (70°C) or higher, thus removing this hot air
from around microwave oven. When the temperature
around the thermal cut-out drops to 104°F (40°C) or
lower, the thermal cut-out shuts off the hood fan motor.
Functions:
1. When the door is opened, the monitor switch
contact close (to the ON condition) due to their
being normally closed. At this time the secondary
interlock relay (RY2), and primary interlock switch
are in the OFF condition (contacts open) due to their
being normally open contact switches. The contacts
of relay (RY1) are in the ON condition (contacts
close).
2. As the door goes to a closed position, the monitor
switch contacts are first opened and then the door
sensing switch and the primary interlock switch
contacts close. (On opening the door, each of these
switches operate inversely.)
3. If the door is opened, and the primary interlock
relay (RY2) and primary interlock switch contacts fail
to open, the monitor fuse blows simultaneously with
closing of the monitor switch contacts.
CAUTION
Before replacing a blown monitor fuse test the
door sensing switch, secondary interlock relay
(RY2), relay (RY1), primary interlock switch and
monitor switch for proper operation. (Refer to
“Test Procedure”).
NOTE
Monitor fuse and switch are replaced as an assembly.
THERMAL CUT-OUT (CAVITY)
This thermal cut-out is located on the top of the oven
cavity. It is designed to prevent damage to the oven unit
if the food in the oven catches fire due to overheating
produced by improper setting of cooking time or failure
of control unit. Under normal operation, the thermal
cut-out remains closed. However, the thermal cut-out
will open at 230°F (110°C) causing the oven to shut
down.
2-6
TURNTABLE MOTOR
The turntable motor rotates the turntable located on
the bottom of the oven cavity, so that the foods on the
turntable cook evenly during cooking. Turntable will turn
in either direction.
COOLING FAN MOTOR
The cooling fan motor drives a blade which draws
external cool air. This cool air is directed through the
air vanes surrounding the magnetron and cools the
magnetron. This air is channelled through the oven
cavity to remove steam and vapors given off from the
heating foods. It is then exhausted through exhausting
air vents at the oven cavity.
HOOD FAN MOTOR
The hood fan motor is a two-speeds, single-phase,
double pole induction type, requiring a hood fan
capacitor. It is located outside the upper rear part of
the oven cavity. The hood fan motor removes hot air
from around the oven as it rises from the conventional
electric or gas range over which it is installed. This air is
then expelled either vertically or horizontally through the
customer supplied duct system, or discharged back into
the kitchen.
HOOD LAMP
The hood lamps are mounted at the hood lamp angle on
the base cover. The hood lamps can be turned off and
on.
Section 2 Operation
2. Operational Principle of Absolute Humidity Sensor:
The figure below shows the basic structure of an
absolute humidity sensor. A bridge circuit is formed
by two thermistors and two resistors (R1 and R2).
The output of the bridge circuit is to be amplified by
the operational amplifier. Each thermistor is
supplied with a current to keep it heated at about
150°C (302°F), the resultant heat is dissipated in the
air and if the two thermistors are placed in different
humidity conditions they show different degrees of
heat conductivity leading to a potential difference
between them, causing an output voltage from the
bridge circuit, the intensity of which is increased as
the absolute humidity of the air increases. Since the
output is very minute, it is amplified by the
operational amplifier.
R3
R2
S : Thermistor
open vessel
C : Thermistor
closed vessel
40
R 99
300k
41
R 100
150k
42
R 101
75k
43
R 102
37.4k
44
C . Thermistor in
closed vessel
S . Thermistor in
open vessel
R 97
47k
Humidity (g/m 2 )
Figure 2-5. Humidity Sensor Operation
F-1
C
R96
F-3
3.57k
S
F-2
21
C91
S
humidity vs, out put voltage
characteristic
C90
Operational
amplifier
Output
voltage
+
620k
R 98
R91
3.32k R92
1.8k
+
IC 2
R93
360k
S W1
P 50
P 51
P 52
P 53
P 54
S W2
S W3
S W4
S W5
AIN6
LS I
(IC 1)
R94
R95
10k
47k
19
AIN4
D90
R 90
R1
Output voltage
C
Humidity sensor circuit:
0.01uF
Figure 2-4. Humidity Sensor Diagram
C92
S ensing part
(C losed vessel)
0.1
uF
S ensing part
(Open vessel)
0.01uF
Thermistors
Ventilation opening for sensing
0.015uF
1. Structure of Absolute Humidity Sensor:
The absolute humidity sensor includes two
thermistors as shown in the illustration below. One
thermistor is housed in the closed vessel filled with
dry air while another in is the open vessel. Each
sensor is provided with the protective cover made of
metal mesh to be protected from the external
airflow.
(3) Detector Circuit of Absolute Humidity Sensor
Circuit:
This detector circuit is used to detect the output
voltage of the humidity circuit to allow the LSI to
control sensor cooking of the unit. When the unit is
set in the sensor cooking mode, 32 seconds of
clearing cycle occurs then the detector circuit starts
to function and the LSI observes the initial voltage
available at its P65 terminal. With this voltage given,
the switches SW1 to SW5 in the LSI are turned on
in such a way as to change the resistance values in
parallel with P58 to P62 of IC2. Changing the
resistance values results in that there is the same
potential at both F-3 terminals of the humidity
sensor and P66 terminal of the LSI. The voltage of
P65 terminal will indicate about -2.5V. This initial
balancing is set up about 32 seconds after the unit
is put in the Sensor Cooking mode. As the sensor
cooking proceeds, the food is heated to generate
moisture by which the resistance balance the bridge
circuit is deviated to increase the voltage available
at P65 terminal of the LSI. Then the LSI observes
that voltage at P65 terminal and compares it with its
initial value, and when the comparison rate reaches
the preset value (fixed for each menu to be cooked),
the LSI causes the unit to stop sensor cooking;
thereafter, the unit goes in the next operation
automatically. When the LSI starts to detect the
initial voltage at P65 terminal 32 seconds after the
unit has been put in the Sensor Cooking mode, if it
is not possible to balance the bridge circuit due to
disconnection of the humidity sensor, ERROR will
appear on the display and the cooking is stopped.
C93
Humidity Sensor Circuit
VA : -15V
VA : -15V
VC : -5V
2-7
Section 2 Operation
Notes
2-8
Section 3 Troubleshooting and Testing
Troubleshooting Guide
When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the
checks. Many of the possible causes of trouble will require that a specific test be performed. These tests are
given a procedure letter which will be found in the “Test Procedure “section.
CAUTION
If the oven becomes inoperative because of a blown monitor fuse, check monitor switch, relay (RY1)
secondary interlock relay (RY2), stop switch (door sensing switch) and primary interlock switch before
replacing the monitor fuse. If the monitor fuse is replaced, the monitor switch must also be replaced.
WARNING
Whenever troubleshooting is performed with the power supply cord disconnected. It may in, some
cases, be necessary to connect the power supply cord after the outer case has been removed, in this
event:
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds and then short-circuit the connection of
the high-voltage capacitor (that is the connecting lead of the high-voltage rectifier) against the
chassis with the use of an insulated screwdriver.
4. Disconnect the leads to the primary of the power transformer.
5. Ensure that the leads remain isolated from other components and oven chassis by using
insulation tape.
WARNING
When the testing is completed:
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds and then short-circuit the connection of
the high-voltage capacitor (that is the connecting lead of the high-voltage rectifier) against the
chassis with the use of an insulated screwdriver.
4. Reconnect the leads to the primary of the power transformer.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the presence of microwave energy within a cavity, place a cup
of cold water on the oven turntable, close the door and set the power to HIGH and then set the microwave timer for
two (2) minutes. When the two minutes has elapsed (timer at zero) carefully check that the water is now hot. If the
water remains cold carry out Before Servicing procedure and re-examine the connections to the component being
tested.
When all service work is completed and the oven is fully assembled, the microwave power output should be checked
and a microwave leakage test should be carried out.
3-1
Section 3 Troubleshooting and Testing
C K = C heck / R E = R eplace
MIC ROWAVE
C OOKING
C ONDITION
Oven seems to be operating but little or
no heat is produced in oven load. (Food
incompletely cooked or not cooked at all
at end of cook cycle.)
Oven goes into a cook cycle but extremely uneven heating is produced in oven
load (food).
Variable cooking does not operate properly except 100% power level mode.
Function of AUTO DE FR OS T does not
operate properly.
S tirrer motor does not operate. (Other
parts operate.)
Oven goes into AUTO DE FR OS T but
food is not defrosted well.
S E NS OR
C OOKING
C ONDITION
The oven stops and "E R R OR " is displayed or does not end during S ensor
C ooking condition. (Oven does not shut
off after a cup of water is boiling by S ensor C ooking.)
Oven stops at 32 seconds after starting.
3-2
HUMI DITY S E NS OR
Oven does not go into cook cycle when
S TAR T pad is touched.
Q
Turntable motor does not operate (Oven
lamp lights and fan motor operate.)
P
NOIS E FILTE R
C K LOW VOLTAG E
C K NO P OWE R AT OUTLE T
Fan motor does not operate. (Oven lamp
and turntable motor operate.)
R E S HOR TE D IN P OWE R C OR D
C K OP E NE D OR S HOR TE D WIR ING
C K HOOD MOTOR C AP AC ITOR
R E HOOD LAMP OR S OC KE T
C K TUR NTABLE OFF C ONDITION
R E S TIR R E R MOTOR
R E TUR NTABLE MOTOR
FAN MOTOR
Oven lamp does not light in cook cycle.
(But it does light when door is opened.)
OVE N LAMP OR S OC KE T
FOIL P ATE R N ON P .W.B.
R E LAY (R Y-5, R Y-6)
R E LAY (R Y-3)
S peed of the hood fan motor does not
change when the Vent hi/lo/off pad is
touched for this function.
N
Hood fan motor does not rotate at all with
touched Vent hi/lo/off pad.
RE
RE
O
N
IDLE
C ONDITION
N
N
Hood lights do not turn on when Light
hi/lo/off pad is pressed.
R E LAY (R Y-4)
R E LAY (R Y-7)
R E LAY (R Y-2)
R E LAY (R Y-1)
Temperature of oven base seems more
than 140ºF (60ºC) because of operation
of the range below. But hood fan motor
does not turn on automatically. (Normally, food fan motor should be operating at
low speed.)
N
N
M
Hood fan motor operates when power
cord is first plugged into wall receptacle.
KE Y UNIT (ME MBR ANE S WITC H)
C ONTR OL UNIT
HOOD FAN MOTOR
Oven lamp does not light with door is
opened.
J
Display does not operate properly when
S TOP clear pad is touched. (The time of
day should appear on the display with
beep sound during normal condition.)
L
K
OFF
C ONDITION
HOOD T HE R MAL C UT-OUT
MONITOR FUS E
MONITOR S WITC H
Display does not illuminate when power
cord is first plugged into wall receptacle.
I
H
G
Monitor fuse blows when power cord is
plugged into wall receptacle.
S E C ONDAR Y INTE R LOC K S YS TE M
P R IMAR Y INTE R LOC K S WITC H
TEMPERATURE FUSE OR THERMAL CUT-OUT
P R OBLE M
Home fuse blows when power cord is
plugged into wall receptacle.
HIG H VOLTAG E C AP AC I TOR
H.V. R E C TIFIE R
P OWE R TR ANS FOR ME R
MAG NE TR ON
P OS S IBLE C AS E AND
DE FE CTIVE P AR TS
C ONDITION
F
E
D
C
B
A
TE S T P R OC E DUR E
Section 3 Troubleshooting and Testing
Test Procedures
Procedure
Letter
A
Component Test
MAGNETRON ASSEMBLY TEST
WARNING
High voltages are present during the cook cycle, so extreme caution should be
observed. Discharge the high voltage capacitor before touching any oven components
or wiring.
1.
2.
3.
4.
5.
6.
7.
8.
9.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity
check across the magnetron filament leads should indicate less than 1 ohm.
To test for a shorted magnetron, connect the ohmmeter leads between the magnetron filament
leads and chassis ground. This test should indicate an infinite resistance. If there is little or no
resistance the magnetron is grounded and must be replaced.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
MICROWAVE OUTPUT POWER
Power output of the magnetron can be measured by performing a water temperature rise test. This
test should only be used if above tests do not indicate a faulty magnetron and there is no defect in
the following components or wiring: silicon rectifier, high voltage capacitor and power transformer.
This test will require a 16 ounce (453 cc.) measuring cup and an accurate mercury thermometer or
thermocouple type temperature tester. For accurate results, the following procedure must be
followed carefully:
1. Fill the measuring cup with 16 oz. (453 cc.) of tap water and measure the temperature of
the water with a thermometer or thermocouple temperature tester. Stir the thermometer or
thermocouple through the water until the temperature stabilizes. Record the temperature of the
water.
2. Place the cup of water in the oven. Operate oven at 100% POWER selecting more than 60
seconds cook time. Allow the water to heat for 60 seconds, measuring with a stop watch,
second hand of a watch or the digital read-out countdown.
3. Remove the cup from the oven and again measure the temperature, making sure to stir the
thermometer or thermocouple through the water until the maximum temperature is recorded.
4. Subtract the cold water temperature from the hot water temperature. The normal result should
be 29.2 to 54.2°F (16.2 to 30.1°C) rise in temperature. If the water temperatures are accurately
measured and tested for the required time period the test results will indicate if the magnetron
tube has low power output (low rise in water temperature) which would extend cooking time or
high power output (high rise in water temperature) which would reduce cooking time. Because
cooking time can be adjusted to compensate for power output, the magnetron tube assembly
should be replaced only if the water temperature rise test indicates a power output well beyond
the normal limits. The test is only accurate if the power supply line voltage is 120 volts and the
oven cavity is clean.
3-3
Section 3 Troubleshooting and Testing
Procedure
Letter
B
Component Test
POWER TRANSFORMER TEST
WARNING
Do not touch the components of the power transformer while power transformer is
energized. It is dangerous because this has high voltage components. (High voltages
are present at the high voltage terminal, so do not attempt to measure the filament
and high voltage.)
1.
2.
3.
4.
5.
6.
7.
8.
C
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Disconnect the primary input terminals and measure the resistance of the transformer with an
ohmmeter. Check for continuity of the coils with an ohmmeter. On R x 1 scale, the resistance of
the primary coil should be less than 1 ohm and the resistance of the high voltage coil should be
approximately 105.5 ohms for RTRN-A779WRZZ, 100 ohms for RTRN-A765WRZZ; the resistance
of the filament coil should be less than 1 ohm.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
HIGH VOLTAGE RECTIFIER TEST
1.
2.
3.
4.
5.
6.
7.
8.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Isolate the rectifier from the circuit. Using the highest ohm scale of the meter, read the
resistance across the terminals and observe, reverse the leads to the rectifier terminals and
observe meter reading. If a short is indicated in both directions, or if an infinite resistance is
read in both directions, the rectifier is probably defective and should be replaced.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
NOTE
Be sure to use an ohmmeter that will supply a forward bias voltage of more than 6.3 volts.
3-4
Section 3 Troubleshooting and Testing
Procedure
Letter
D
Component Test
HIGH VOLTAGE CAPACITOR TEST
1.
2.
3.
4.
5.
6.
7.
8.
E
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input
leads and check for short or open between the terminals using an ohmmeter.
Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate
continuity for a short time and should indicate an open circuit once the capacitor is charged. If
the above is not the case, check the capacitor with an ohmmeter to see if it is shorted between
either of the terminals and case. If it is shorted, replace the capacitor.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
THERMAL CUT-OUT AND TEMPERATURE FUSE TEST
CAVITY THERMAL CUT-OUT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. A continuity check across the thermal cut-out terminals should indicate a closed circuit unless
the temperature of the thermal cut-out reaches approximately 293°F(145°C). An open thermal
cut-out indicates overheating of the oven, exchange the oven thermal cut-out and check inside
of oven cavity and for improper setting of cooking time or operation of control unit. Check for
restricted air flow through the vent holes of the oven cavity, especially the cooling fan and air
guide.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
MAGNETRON TEMPERATURE FUSE TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. A continuity check across the magnetron temperature fuse terminals should indicate a closed
circuit unless the temperature of the magnetron temperature fuse reaches approximately
302°F(150°C). An open magnetron temperature fuse indicates overheating of the magnetron.
Check for restricted air flow to the magnetron, especially the cooling fan air guide.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
CAUTION
If the temperature fuse indicates an open circuit at room temperature, replace
temperature fuse.
3-5
Section 3 Troubleshooting and Testing
Procedure
Letter
F
Component Test
PRIMARY INTERLOCK SWITCH TEST
1.
2.
3.
4.
5.
6.
7.
8.
G
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO)
terminal of the switch. The meter should indicate an open circuit with the door open and a
closed circuit with the door closed. If improper operation is indicated, replace the secondary
interlock switch.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
PRIMARY INTERLOCK SYSTEM TEST
STOP SWITCH (DOOR SENSING SWITCH)
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO)
terminal of the switch. The meter should indicate an open circuit with the door open and a
closed circuit with the door closed. If improper operation is indicated, replace the door sensing
switch.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
CAUTION
If the door sensing switch contacts fail in the open position and the door is closed, the
cooling fan motor, stirrer motor and oven light will be activated by RY1.
SECONDARY INTERLOCK RELAY (RY2)
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Disconnect two (2) wire leads from the male tab terminals of the Secondary Interlock Relay.
Check the state of the relay contacts using an ohmmeter. The relay contacts should be open.
If the relay contacts are closed, replace the circuit board entirely or the relay itself.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
3-6
Section 3 Troubleshooting and Testing
Procedure
Letter
H
Component Test
MONITOR SWITCH TEST
1.
2.
3.
4.
5.
6.
7.
8.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Before performing this test, make sure that the secondary interlock switch and the primary
interlock relay are operating properly, according to the above Switch Test Procedure. Disconnect
the wire lead from the monitor switch (COM) terminal. Check the monitor switch operation by
using the ohmmeter as follows. When the door is open, the meter should indicate a closed
circuit. When the monitor switch actuator is pushed by a screwdriver through the lower latch
hole on the front plate of the oven cavity with the door opened (in this condition the plunger of
the monitor switch is pushed in), the meter should indicate an open circuit. If improper
operation is indicated, the switch may be defective. After testing the monitor switch, reconnect
wire lead to monitor switch (COM) terminal and check continuity of monitor circuit.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
White
Screwdriver
Yellow
Monitor
Switch
Primary
Interlock
Switch
I
Ohmmeter
BLOWN MONITOR FUSE TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
If the monitor fuse is blown when the door is opened, check the primary interlock switch,
secondary interlock relay (RY2), relay (RY1) and monitor switch according to the “TEST
PROCEDURE” for those switches before replacing the blown monitor fuse.
CAUTION
Before replacing a blown monitor fuse, test the primary interlock switch, secondary
interlock relay, door sensing switch and monitor switch for proper operation.
5.
6.
7.
8.
If the monitor fuse is blown by improper switch operation, the monitor fuse and monitor switch
must be replaced with “monitor fuse and monitor switch assembly FFS-BA041WRKZ or FFSBA042WRKZ even if the monitor switch operates normally.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
3-7
Section 3 Troubleshooting and Testing
Procedure
Letter
J
Component Test
HOOD THERMAL CUT-OUT TEST
1.
2.
3.
4.
5.
6.
7.
8.
K
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
A continuity check across the thermal cut-out terminals should indicate an open circuit unless
the temperature of the thermal cut-out reaches approximately 140°F(60°C) or more. At that
temperature, the contacts will close. The thermal cut-out opens automatically at approximately
113°F(45°C).
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
HOOD FAN MOTOR TEST
1.
2.
3.
4.
5.
6.
7.
8.
Disconnect power supply cord, and remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
If the motor does not turn, touch the FAN pad once and check voltage between pins “1” and
“2” (Blue and Black wires) of the 6 pin connector. If 120 Volts appear and the hood capacitor
is good, replace the hood fan assembly. If 120 Volts does not appear, check the motor circuit.
The resistance values of motor terminals are shown below:
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect power supply cord after the outer case is installed.
Run oven and check all functions.
YLW
BLU
1
4
Hood Fan
Capacitor
32
5
RED
45
20
2
BLK
R esistance between;
BLU (1) AND
BLK (2) AND
BLU (1) AND
BLK (2) AND
WHT (3) AND
YLW (4) = 0 (S horted)
YLW (4) = 32
BLK (2) = 32
WHT (3) = 20
R E D (5) = 45
BLU BLK WHT
1
2
3
6-P IN C ONNE C TOR
OF HOOD FAN MOTOR
3
WHT
3-8
4
5
YLW R E D
Section 3 Troubleshooting and Testing
Procedure
Letter
L
Component Test
TOUCH CONTROL PANEL ASSEMBLY TEST
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc.
Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only
a voltmeter and ohmmeter. In this service manual, the touch control panel assembly is divided into
two units, Control Unit and Key Unit, and troubleshooting by unit replacement is described
according to the symptoms indicated.
Before testing,
1. Disconnect power supply cord, and remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Disconnect the leads to the primary of the power transformer.
5. Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
6. After that procedure, re-connect the power supply cord.
KEY UNIT (Membrane Switch)
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Check key unit ribbon connection before replacement.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
The following symptoms indicate a defective key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
If the key unit is defective.
1. Disconnect the power supply cord and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Replace the key unit (membrane switch).
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the covers (outer case cabinet and control unit cover)
are installed.
8. Run the oven and check all functions.
3-9
Section 3 Troubleshooting and Testing
Procedure
Letter
L
Component Test
CONTROL UNIT
The following symptoms indicate a defective control unit. Before replacing the control unit, perform
the Key unit test (Procedure M) to determine if control unit is faulty.
1. In connection with pads.
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
2. In connection with indicators.
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
3. Other possible problems caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
When testing is completed,
1.
2.
3.
4.
5.
6.
7.
3-10
Disconnect the power supply cord and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Reconnect all leads removed from components during testing.
Re-install the outer case (cabinet).
Reconnect the power supply cord after the case is installed.
Run the oven and check all functions.
Section 3 Troubleshooting and Testing
Procedure
Letter
M
Component Test
KEY UNIT (FPC) TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
If the display fails to clear when the CLEAR-OFF pad is depressed, first verify the flat ribbon
cable is making good contact, verify that the door sensing switch (stop switch) operates
properly; that is the contacts are closed when the door is closed and open when the door is
open. If the door sensing switch (stop switch) is good, disconnect the flat ribbon cable that
connects the key unit to the control unit and make sure the door sensing switch is closed
(either close the door or short the door sensing switch connector). Use the Key unit matrix
indicated on the control panel schematic and place a jumper wire between the pins that
correspond to the CLEAR-OFF pad making momentary contact. If the control unit responds by
clearing with a beep the key unit is faulty and must be replaced. If the control unit does not
respond, it is faulty and must be replaced. If a specific pad does not respond, the above
method may be used (after clearing the control unit) to determine if the control unit or key pad
is at fault.
Reconnect all leads removed from components during testing.
Re-install the control panel assembly.
Reconnect the power supply cord.
Run the oven and check all functions.
5.
6.
7.
8.
59
58
57
56
55
54
53
52
G5
G6
G7
G8
G9
G 10
G 11
G 12
user
pref
auto
cook
auto
defrost
vegetables
3
6
9
S TOP
clear
power
level
0
60
G4
61
G3
62
G2
turn table
on-off
sensor
reheat
snack
menu
baked
potato
2
5
8
1
G1
timer
On-off
sensor
cook
chicken
nuggets
pop
corn
1
4
7
S TART
enter
+30 sec
51 G 13
KE Y UNIT
3-11
Section 3 Troubleshooting and Testing
Procedure
Letter
N
Component Test
RELAY TEST
1.
2.
3.
4.
5.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Disconnect the leads to the primary of the power transformer.
Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
6. After that procedure, re-connect the power supply cord.
7. Remove the outer case and check voltage between Pin No. 3 of the 3 pin connector (CN-C) and
the lower side terminal of the relay RY-1 on the control unit with an A.C. voltmeter.
The meter should indicate 120 volts, if not check oven circuit.
RY1 and RY2 Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
DC. voltage indicated.......................... Defective relay.
DC. voltage not indicated ................... Check diode which is connected to the relay coil. If diode is
good, control unit is defective.
RELAY SYMBOL
RY -1
RY -2 (COOK)
RY -3
RY -4
RY -5, RY-6
RY -7
8.
9.
10.
11.
12.
13.
14.
15.
3-12
OPERATIONAL VOLTAGE
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
CONNECTED COMPONENTS
Oven lamp / Fan motor / Stirrer motor
Power transformer
Hood motor (HIGH/LOW selection)
Hood motor
Hood lamp
Turntable motor
If any abnormal condition is detected, replace the control unit.
Disconnect the power supply cord and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Reconnect all leads removed from components during testing.
Re-install the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
Section 3 Troubleshooting and Testing
Procedure
Letter
O
Component Test
FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary
on the PWB, this foil pattern acts as a fuse.
Fuse check and repairs.
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
4. Remove the control unit.
5. Follow the troubleshooting guide given below for repair.
STEPS
1
2
OCCURRENCE
Only pattern at “a” is broken.
Pattern at “a” and “b” are broken.
CAUSE OR CORRECTION
*Insert jumper wire J1 and solder.
Replace the control unit.
CN C
6. Make a visual inspection of varistor. Check for
burn damage and examine the transformer with
a tester for the presence of layer short-circuit
(check the primary coil resistance which is
approximately 215Ω ± 10%). If any abnormal
condition is detected, replace defective parts.
(J1)
b
7. Reconnect all leads removed from components
during testing.
a
8. Re-install the control unit to the control panel
and re-install the control panel to the oven.
9. Reconnect the power supply cord. Run the oven and check all functions.
T1
Follow the troubleshooting guide given below, if indicator does not light up after above
check and repairs are finished.
1. Disconnect the power supply cord and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the leads to the primary of the power transformer. Ensure that these leads remain
isolated from other components and oven chassis by using insulation tape.
5. After that procedure, re-connect the power supply cord.
6. Follow the troubleshooting guide given below for repair.
STEPS
7.
8.
9.
10.
11.
12.
13.
OCCURRENCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present between Pin No. 3 of
the 3 -pin connector (CN -C) and lower side terminal of relay RY -1
Check supply voltage and oven power cord.
2
The rated AC voltage is present at primary side of low voltage
trans former.
Low voltage transformer or secondary circuit defective.
Check and replace the control unit.
Disconnect the power supply cord.
Open the door and block it open.
To discharge high voltage capacitor, wait for 60 seconds.
Reconnect all leads removed from components during testing.
Re-install the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
3-13
Section 3 Troubleshooting and Testing
Procedure
Letter
P
Component Test
HUMIDITY SENSOR TEST
Checking the initial sensor cooking condition:
WARNING
The oven should be fully assembled before following procedure.
1. The oven should be plugged in at least two minutes before sensor cooking.
2. Room temperature should not exceed 35°C.
3. The unit should not be installed in any area where heat and steam are generated. The
unit should not be installed, for example, next to a conventional surface unit. Refer to the
“INSTALLATION Instructions”.
4. Exhaust vents are provided on the back of the unit for proper cooling and air flow in the cavity.
To permit adequate ventilation, be sure to install so as not to block these vents. There should
be some space for air circulation.
5. Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any
moisture with a dry cloth or paper towel.
6. The Sensor works with food at normal storage temperature. For example, chicken pieces would
be at refrigerator temperature and canned soup at room temperature.
7. Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings. The
sensor will detect the vapor given of by the spray and turn off before food is properly cooked.
8. After the oven is started on sensor cooking condition, if the sensor has not detected the vapor
of the food, ERROR will appear and the oven will shut off.
Water load cooking test:
WARNING
The oven should be fully assembled before following procedure.
Make sure the oven has been plugged in at least two minutes before checking sensor cook
operation. The cabinet should be installed and screws tightened.
1.
2.
3.
4.
Fill approximately 200 milliliters of tap water in a 1000 milliliter measuring cup.
Place the container on the center of tray in the oven cavity.
Close the door.
Touch the Timer On-Off pad once, the POWER LEVEL pad twice and the START pad once. And
touch the number pads 1 once and the number pad 2 once. Now, the oven is in the sensor
cooking condition, and “AH10” and “COOK” will appear in the display.
5. The oven will operate for the first 32 seconds, without generating microwave energy.
NOTE
ERROR will appear if the door is opened or STOP/CLEAR pad is touched during first
stage of sensor cooking.
6. After approximately 32 seconds, microwave energy is produced. If ERROR is displayed or
the oven does not turn off, replace the humidity sensor or check the control unit, refer to
explanation below.
3-14
Section 3 Troubleshooting and Testing
Procedure
Letter
P
Component Test
TESTING METHOD FOR HUMIDITY SENSOR AND/OR CONTROL UNIT
To
1.
2.
3.
4.
5.
6.
7.
8.
9.
determine if sensor is defective, the simplest method is to replace it with a new sensor.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Remove the humidity sensor.
Install the new humidity sensor.
Reconnect all leads removed from components during testing.
Re-install the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Reconnect the oven to the power supply and check the sensor cook operation as follows:
a. Fill approximately 200 milliliters of tap water in a 1000 milliliter measuring cup.
b. Place the container on the center of tray in the oven cavity.
c. Close the door.
d. Touch the Timer On-Off pad once, the POWER LEVEL pad twice and the START pad once.
And touch the number pads 1 once and the number pad 2 once.
e. The control panel is in automatic Sensor operation.
f. The oven turns off automatically, and the time for detecting moisture will be displayed.
If new sensor dose not operate properly, the problem is with the control unit, and refer to
explanation below.
CHECKING CONTROL UNIT
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the sensor connector that is mounted to control panel.
5. Then connect the dummy resistor circuit (see below ) to the sensor connector of control panel.
P lunger
NC
NO
R1,R2: 22Ω ±1% 1/2W
R3: 4.3kΩ ±5% 1/4W
F-1
F-2
R4: 1MΩ ±% 1/4W
F-3
To connector (F)
on C ontrol Unit.
1
2
3
R1
C ONNE C TOR
R2
C OM
C OM NO
R3
R4
NC
Sensor Dummy Resistor Circuit
3-15
Section 3 Troubleshooting and Testing
Procedure
Letter
Component Test
6. Disconnect the leads to the primary of the power transformer.
7. Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
8. After that procedure, re-connect the power supply cord.
9. Check the sensor cook operation proceed as follows:
a) Close the door. Touch the Timer On-Off pad once, the POWER LEVEL pad twice and the START
pad once. And touch the number pads 1 once and the number pad 2 once.
b) The control panel is in the sensor cooking operation.
c) After approximately 41 seconds, push plunger of select switch for more than 3 seconds. This
condition is same as judgement by humidity sensor.
d) After approximately 3 seconds, the display shows “X X. X X “ which is the time for detecting
moisture.
If the above is not the case, the control unit is probably defective.
If the above is proper, the humidity sensor is probably defective.
10. Disconnect the power supply cord, and then remove outer case.
11. Open the door and block it open.
12. Discharge high voltage capacitor.
13. Disconnect the dummy resistor circuit from the sensor connector of control panel.
14. Carry out necessary repair.
15. Reconnect all leads removed from components during testing and repairing.
16. Re-install the outer case (cabinet).
17. Reconnect the power supply cord after the outer case is installed. Run the oven and check all
functions.
18. Carry out “Water load cooking test” again and ensure that the oven works properly.
Q
NOISE FILTER TEST
1.
2.
3.
4.
5.
6.
7.
8.
9.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor. (See Warnings and Instructions on page 3-1)
Disconnect the leads to the primary of the power transformer.
Using an ohmmeter, check between the terminals as described in the following table.
If incorrect readings are obtained, replace the noise filter.
Reconnect all leads removed from components
NOISE FILTER
H
N
during testing.
MONITOR
RESISTOR
FUSE
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the
outer case is installed.
LINE CROSS CAPACITOR
Run the oven and check all functions.
NOISE SUPPRESSION COIL
LINE BYPASS
CAPACITOR
0.0033μF / 250V
LOAD
MEASURING POINT
Between N and H
Between terminal N and LOAD
Between terminal L and LOAD
3-16
LINE BYPASS
CAPACITOR
0.0033μF / 250V
LOAD
INDICATION OF OHMMETER
Open circuit.
Short circuit.
Short circuit.
Section 4 Component Teardown
WARNING
To prevent an electric shock, take the following precautions:
1. Before wiring:
A. Disconnect the power supply.
B. Open the door and wedge the door open.
C. Discharge the high voltage capacitor and wait for 60 seconds.
2. DO NOT let wire leads touch to the following parts:
A. High voltage parts: Magnetron, High voltage transformer, High voltage capacitor and High
voltage rectifier assembly.
B. Hot parts: Oven lamp, Magnetron, High voltage transformer and Oven cavity.
C. Sharp edge: Bottom plate, Oven cavity, Waveguide flange, Chassis support and other metallic
plates.
D. Movable parts (to prevent a fault) Fan blade, Fan motor, Switch, Switch lever, Open button.
3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector completely until its pin is locked. Make sure that the wire leads
should not come off even if the wire leads are pulled.
5. To prevent an error function, connect the wire leads correctly, referring to the Pictorial Diagram.
WARNING
Avoid possible exposure to microwave energy. Please follow instructions below before operating oven.
1. Disconnect the power supply cord.
2. Make sure that a definite” click” can be heard when the microwave oven door is unlatched.
(Hold the door in a closed position with one hand, then push the door open button with
the other, this causes the latch leads to rise, it is then possible to hear a “click’ as the door
switches operate.)
3. Visually check the door and cavity face plate for damage (dents, cracks, signs of arcing etc.).
Carry out any remedial work that is necessary before operating the oven.
Do not operate the oven if any of the following conditions exist;
1. Door does not close firmly.
2. Door hinge, support or latch hook is damaged.
3. The door gasket or seal is damaged.
4. The door is bent or warped.
5. There are defective parts in the door interlock system.
6. There are defective parts in the microwave generating and transmission assembly.
7. There is visible damage to the oven.
Do not operate the oven:
1. Without the RF gasket (Magnetron).
2. If the wave guide or oven cavity are not intact.
3. If the door is not closed.
4. If the outer case (cabinet) is not fitted.
CAUTION
Disconnect oven from power supply before removing outer case. Discharge high voltage capacitor
before touching any oven components or wiring after removing outer case.
4-1
Section 4 Component Teardown
Removal Of Oven From Wall
NOTE
The following adjustments or component replacement
can be performed without removing the oven from the
wall.
1. Hood lamps, sockets, grease filter.
2. Oven lamp, Base cover and hood lamp glass
assembly.
3. Turntable motor.
4. Hood exhaust louver.
5. Control panel assembly or components.
Hood Exhaust Louver Removal
1. Disconnect the power supply cord.
2. Open the oven door and block it open.
3. To discharge the high voltage capacitor, wait for 60
seconds.
4. Remove the one (1) screw holding the outer case
cabinet to the oven cavity front face plate (the
position is front/ center on the outer case cabinet).
5. Remove the two (2) screws holding the hood louver
to the oven cavity.
6. Remove the hood louver from the over by pushing
the right and left tabs of the hood louver.
7. Now, the hood louver is free.
Screw
Outer Case Cabinet
Screw
Hood Exhaust Louver
1. Disconnect the power supply cord, and uncoil the
power supply cord.
2. To discharge the high voltage capacitor, wait for 60
seconds.
3. Remove the turntable tray and support from the
oven cavity.
4. While supporting the front of the oven, unfasten
the two (2) screws holding the oven to the unit
mounting plate.
5. Remove the oven from the unit mounting plate and
pull the power cord out of the wall cabinet.
6. The oven is now free and can be placed on the work
surface selected for servicing the oven.
7. Installation is the reverse of this procedure.
Outer Case Removal
Remove the oven from the wall and proceed as follows:
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. To discharge the high voltage capacitor, wait for 60
seconds.
4. Remove three (3) screws holding the hood exhaust
louver to the oven. (Refer to procedure of “HOOD
EXHAUST LOUVER REMOVAL”.)
5. Remove four (4) screws holding the rear stay to the
hood fan motor or the oven, and remove it.
6. Remove the four (4) screws from the rear of the
outer case cabinet.
7. Disconnect the three (3) pin connector of the power
supply cord from the wiring harness and remove the
power supply cord together with the outer case.
8. Discharge high voltage capacitor.
CAUTION
Screw
Figure 4-1.
4-2
(Two persons recommended to remove the oven)
Discharge the high voltage capacitor before
touching any oven components or wiring.
Section 4 Component Teardown
Power Transformer Removal
REMOVAL
1. Disconnect the power supply cord, remove the oven
from wall, and remove outer case. (Refer to
procedure of “Removal Of Oven From Wall” and
“Outer Case Removal”.) And proceed as follows.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove one (1) screw holding the hood duct to the
oven cavity front flange.
5. Disconnect the stop switch harness from the chassis
support and disconnect the wire leads from the fan
motor.
6. Lift up the fan motor side of the hood duct.
7. Disconnect filament leads of transformer from the
magnetron and capacitor.
8. Disconnect high voltage leads of capacitor from the
transformer.
9. Disconnect wire leads from transformer.
10. Remove two (2) screws holding the transformer to
right base plate.
RE-INSTALL
1. Install by sliding transformer on the right base plate
with its primary terminals toward the outer case.
2. Secure the transformer with two (2) screws to right
base plate.
3. Re-connect wire leads (primary and high voltage)
to the transformer and filament leads of transformer
to magnetron and high voltage capacitor. Refer to
“PICTORIAL DIAGRAM”.
4. Re-install the hood duct holding the fan motor to the
oven cavity front flange with one (1) screw.
5. Re-connect the wire leads to the chassis support and
the fan motor, referring to “PICTORIAL DIAGRAM”.
6. Re-install the outer case and check that oven is
operating properly.
CAUTION
Make sure the wire leads never touch the fan
blade.
Hood Fan Motor, Hood Duct, Oven Lamp
Socket And Ah Sensor Removal
1. Disconnect the power supply cord and remove the
oven from wall and remove outer case. (Refer to
procedure of “Removal of Oven from Wall” and
“Outer Case Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
HOOD FAN MOTOR
4. Disconnect the 6-pin connector of the hood fan
motor from the main wire harness located at the
right edge of the hood duct and release the snap
band from the hood duct.
5. Lift hood fan motor from hood duct.
6. Now, the hood fan motor is free.
HOOD DUCT
7. Disconnect the connector CN-F from the control unit.
8. Remove one (1) screw holding the hood duct to the
oven cavity front plate.
9. Release the 6-pin connector and the 3-pin connector
of the main harness A from the hood duct.
10. Disconnect the wire leads from the fan motor and
chassis support, and release the wire leads from
holes of the hood duct.
11. Remove two (2) unit mounting screws from chassis
support (right side) and the hood duct (left side).
12. Remove one (1) screw holding the chassis support.
13. Remove the chassis support.
14. Remove hood duct from oven cavity by lifting it up.
OVEN LAMP SOCKET
15. Screw the oven lamp off from the lamp socket.
16. Remove the lamp socket from the lamp angle.
17. Pull the wire leads from the oven lamp socket by
pushing the terminal hole of the oven lamp socket
with a small flat type screw driver.
(See Figure 4-2 on next page)
18. Now, the oven lamp socket is free.
Continued on next page.
4-3
Section 4 Component Teardown
Oven Lamp Socket
Terminal
Wire Lead
Terminal Hole
Flat Blade Small Screwdriver
Figure 4-2.
AH SENSOR
19. Release the harness of the AH sensor assembly from
three (3) wire holders of the hood duct.
20. Remove two (2) screws holding the AH sensor
assembly to the hood duct.
21. Now, the AH sensor assembly is free.
Magnetron Removal
1. Disconnect power supply cord, remove oven from
wall and remove outer case (Refer to procedure
of “Removal of Oven from Wall” and “Outer Case
Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Disconnect the wire leads from the fan motor and
the chassis support, and release them from the holes
of hood duct.
5. Remove the one (1) screw holding the hood duct to
the oven cavity front plate, and lift up the fan motor
side of the hood duct.
6. Remove the one (1) screw holding the capacitor
holder to the hood intake duct.
7. Disconnect the high voltage wire leads of the high
voltage rectifier assembly from the magnetron.
4-4
8. Disconnect the filament lead of the transformer from
the magnetron.
9. Remove the power transformer from the right
base plate, referring to “POWER TRANSFORMER
REMOVAL“.
10. Carefully remove four (4) mounting screws holding
the magnetron to waveguide. When removing the
screws hold the magnetron to prevent it from falling.
11. Remove the magnetron from the unit with care so
the magnetron tube should not be hit by any metal
object around the tube.
12. Remove the one (1) screw holding the magnetron air
guide to the magnetron.
13. Remove the magnetron air guide.
CAUTION
When replacing the magnetron, be sure the
R.F. Gasket is in place and mounting screws are
tightened securely.
High Voltage Rectifier And High Voltage
Capacitor Removal
1. Disconnect power supply cord, remove oven from
wall and remove outer case (Refer to procedure
of “Removal of Oven from Wall” and “Outer Case
Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Disconnect the wire leads from the fan motor and
the chassis support, and release them from the holes
of hood duct.
5. Remove the one (1) screw holding the hood duct
to the oven cavity front flange, and lift up the fan
motor side of the hood duct.
6. Disconnect the high voltage wire leads with high
voltage rectifier from the magnetron.
7. Disconnect filament lead of the transformer from
high voltage capacitor.
8. Disconnect high voltage wire from capacitor.
Section 4 Component Teardown
9. Remove one (1) screw holding capacitor holder and
high voltage rectifier to the hood intake duct.
10. Disconnect the high voltage rectifier assembly from
the high voltage capacitor.
11. Now, the high voltage rectifier assembly is free.
12. Remove capacitor from the holder.
13. Now, the high voltage capacitor is free.
CAUTION
When replacing the high voltage rectifier
assembly, the ground side terminal must be
secured firmly with a grounding screw.
Hood Fan Thermal Cut-Out Removal
1. Disconnect power supply cord, remove oven from
wall and remove outer case (Refer to procedure
of “Removal of Oven from Wall” and “Outer Case
Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Disconnect the wire leads from the hood fan thermal
cut-out.
5. Remove one (1) screw holding the thermal cut-out
to the right base plate.
6. Remove the hood fan thermal cut-out from the right
base plate.
7. Remove one (1) screw holding the thermal cut-out
to the bottom plate (outer case side).
8. Now, the hood fan thermal cut-out is free.
Thermal Cut-Out (Cavity) Removal
1. Disconnect power supply cord, remove oven from
wall and remove outer case (Refer to procedure
of “Removal of Oven from Wall” and “Outer Case
Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove two (2) unit mounting screws.
5. Remove the hood duct. (Refer to the procedure of
“HOOD FAN MOTOR, HOOD DUCT AND OVEN LAMP
SOCKET REMOVAL”.
6. Straighten the tab holding the thermal cut-out to the
top plate of the oven cavity.
7. Release the thermal cut-out (cavity) from the one slit
of the oven cavity top plate.
8. Disconnect the wire leads from the thermal cut-out
(cavity).
9. Now, the thermal cut-out (cavity) is free.
NOTE
When the tab is broken or turned off, use the another
tab which is fixed near the slit when the new thermal
cut-out is replaced.
Top of Oven Cavity
Tab
Thermal
Cut-out
Waveguide
Slit
Thermal
Cut-out
(Cavity)
Thermal
Cut-out
Tab
Figure 4-3.
4-5
Section 4 Component Teardown
Cooling Fan Motor Removal
Installation
Removal
1. Install the fan blade to the fan motor shaft according
to the following procedure.
2. Hold the center of the bracket which supports the
shaft of the fan motor on the flat table.
3. Apply screw lock tight into the hole (for shaft) of the
fan blade.
4. Install the fan blade to the shaft of fan motor by
pushing the fan blade with a small, light weight, ball
peen hammer or rubber mallet.
1. Disconnect power supply cord, remove oven from
wall and remove outer case (Refer to procedure
of “Removal of Oven from Wall” and “Outer case
Removal”.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Disconnect the wire leads from the fan motor and
the chassis support.
5. Remove one (1) screw holding the hood duct to
oven cavity.
6. Release wire leads from the hole of the hood duct.
7. Lift up the fan motor side of the hood duct.
8. Remove the two (2) screws holding the fan motor to
the hood duct.
9. Remove the fan blade from the fan motor shaft
according the following procedure.
10. Hold the edge of the rotor of the fan motor by using
a pair of groove joint pliers.
CAUTION
Do not hit the fan blade strongly when installing
because the bracket may be deformed. Make
sure that the fan blade rotates smoothly after
installation. Make sure that the axis of the shaft
is not slanted.
5.
6.
7.
8.
Install fan motor to hood duct with two (2) screws.
Install hood duct to oven cavity with one (1) screw.
Re-install wire leads to the hole of the hood duct.
Connect the wire leads to the fan motor and chassis
support, referring to the pictorial diagram.
9. Refer to procedure of “Outer case Removal“. And
reverse their procedure. Re-install the outer case.
Coil
Groove Joint Pliers
CAUTION
Make sure that any pieces do not enter the gap
between the rotor and the stator of the fan
motor. Because the rotor is easy to be shaven
by pliers and metal pieces may be produced. Do
not touch the pliers to the coil of the fan motor
because the coil may be cut or damaged. Do not
disfigure the bracket by touching with the pliers.
Stator
Gap
Bracket
Rear View
11. Remove the fan blade from the shaft of the fan
motor by pulling and rotating the fan blade with your
hand.
12. Now, the fan blade will be free.
CAUTION
Do not re-use the removed fan blade because
the hole (for shaft) may be larger than normal
Rotor
Shaft
Table
Shaft
Axis
Stator
Rotor
Center of
Bracket
These are the positions
that should be pinched
with pliers.
Side View
Figure 4-4. Fan Motor Components
4-6
Section 4 Component Teardown
Turntable Motor Removal
Stirrer Cover And Stirrer Fan Installation
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Remove the three (3) screws holding the base cover
to the oven cavity.
4. Remove the base cover from the oven cavity by
pulling down and moving to the left slightly.
5. Disconnect the wire leads from the turntable motor.
6. Remove one (1) screw holding turntable motor to
the oven cavity.
7. Now the turntable motor is free.
1. Put the stirrer fan on the stirrer cover to match the
stirrer fan shaft to the center of the stirrer support.
2. Insert the shaft of stirrer fan to the shaft of stirrer
motor.
3. Insert the cutout of stirrer cover to the tabs on the
ceiling.
4. Install the stirrer cover to the oven cavity, and
secure it by one canoe clip.
Stirrer Motor Removal
Shaft
Stirrer Fan
1. Disconnect the power supply cord and remove the
oven from wall and outer case. (Refer to procedure
of “Removal of Oven from Wall” and Outer case
Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
Stirrer Cover
Canoe Clip
Figure 4-5.
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the hood fan motor and the hood duct from
the oven cavity, referring to the procedure of “HOOD
FAN MOTOR, HOOD DUCT AND OVEN LAMP SOCKET
REMOVAL”.
5. Disconnect the wire leads from the stirrer motor.
6. Remove the two (2) screws holding the stirrer motor
to the waveguide of the oven cavity.
7. Remove the stirrer motor from the waveguide.
8. Now, the stirrer motor is free.
9. When installing the stirrer motor, the shaft of stirrer
motor must be inserted to the stirrer fan shaft.
Refer to the procedure of “STIRRER COVER AND
STIRRER FAN INSTALLATION”.
4-7
Section 4 Component Teardown
Positive Lock® Connector (No-Case Type)
Removal
Servicing The Touch Control Panel
1. Disconnect the power supply cord and remove the
oven from wall and outer case. (Refer to procedure
of “Removal of Oven from Wall” and Outer case
Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
This unit uses CMOS LSI in the integral part of the
circuits. When handling these parts, the following
precautions should be strictly followed. CMOS LSI have
extremely high impedance at its input and output
terminals. For this reason, it is easily influenced by the
surrounding high voltage power source, static electricity
charge in clothes, etc. and sometimes it is not fully
protected by the built-in protection circuit.
In order to protect CMOS LSI.
1. When storing and transporting, thoroughly wrap
them in aluminium foil. Also wrap all PW boards in
aluminium foil.
2. When soldering, ground the technician and use a
grounded soldering iron and work table.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Push the lever of positive lock® connector.
5. Pull down on the positive lock® connector.
CAUTION
When connecting the positive lock® connectors
to the terminals, install the positive lock® so
that the lever faces you.
Terminal
Positive Lock
Connector
1
Push
Lever
2
Pull Down
Positive lock®, connector
Figure 4-6. Positive Lock Connector
Precautions For Handling Electronic Components
Servicing of Touch Control Panel
The following are procedures to permit servicing of the
touch control panel of the microwave oven and the
precautions you must take when doing so. To perform
the servicing, power to the touch control panel is
available either from the power line of the oven itself or
from an external power source.
A. Servicing the touch control panel with power
supply of the oven:
CAUTION
The high voltage transformer of the microwave
oven is still live during servicing and presents a
hazard.
Therefore, before checking the performance of the touch
control panel:
1. Disconnect the power supply cord and then remove
the outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4-8
Section 4 Component Teardown
4. Disconnect the leads to the primary of the power
transformer.
5. Ensure that these leads remain isolated from other
components and oven chassis by using insulation
tape.
6. After that procedure, re-connect the power supply
cord.
After checking performance of the touch control
panel:
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Reconnect the leads to the primary of the power
transformer.
4. Reinstall the outer case (cabinet).
5. Reconnect the power supply cord after the outer
case is installed.
6. Run the oven and check all functions.
a) On some models, the power supply cord between
the touch control panel and the oven itself is so
short that the two can’t be separated. For those
models, check and repair all the controls (sensorrelated ones included) of the touch control panel
while keeping it connected to the oven.
b) On some models, the power supply cord between
the touch control panel and the oven proper is long
enough that they may be separated from each other.
For those models, it is possible to check and repair
the controls of the touch control panel while keeping
it apart from the oven proper; in this case you must
short both ends of the door sensing switch (on PWB)
of the touch control panel with a jumper, which
activates an operational state that is equivalent to
the oven door being closed. As for the sensor-related
controls of the touch control panel, checking them is
possible if dummy resistor(s) with resistance equal to
that of the controls are used.
B. Servicing the touch control panel with power
supply from an external power source:
Disconnect the touch control panel completely from the
oven proper, and short both ends of the door sensing
switch (on PWB) of the touch control panel, which brings
about an operational state that is equivalent to the oven
door being closed. Connect an external power source to
the power input terminal of the touch control panel, then
it is possible to check and repair the controls of the touch
control panel; it is also possible to check the sensorrelated controls of the touch control panel by using the
dummy resistor(s).
Servicing Tools
Tools required to service the touch control panel
assembly.
1. Soldering iron: 60W (It is recommended to use a
soldering iron with a grounding terminal.)
2. Oscilloscope: Single beam, frequency range:
DC - 10MHz type or more advanced model.
3. Others: Hand tools
Other Precautions
1. Before turning on power source of the control unit,
remove the aluminium foil applied for preventing
static electricity.
2. Connect the connectors of the key unit to the control
unit, being sure that the lead wires are not twisted.
3. After aluminium foil is removed, be careful that
abnormal voltage due to static electricity etc. is not
applied to the input or output terminals.
4. Attach connectors, electrolytic capacitors, etc. to
PWB, making sure that all connections are tight.
5. Be sure to use specified components where high
precision is required.
4-9
Section 4 Component Teardown
Control Panel Assembly And Control Unit
Removal
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Remove one (1) screw holding the hood exhaust
louver to oven cavity front flange.
4. Remove the hood exhaust louver from the oven by
pushing the right and left tabs of the hood exhaust
louver. (Refer to procedure of “HOOD EXHAUST
LOUVER REMOVAL”)
5. Remove one (1) screw holding the control panel to
the oven cavity front face plate.
6. Release the control panel from the oven cavity front
face plate by lifting it up.
7. Disconnect the wire leads from the relays RY1 and
RY2.
8. Disconnect the connectors CN-A, CN-B, CN-C, CN-E
and CN-F from the control unit.
9. Remove the control panel assembly from the oven.
10. Now, the control panel assembly is free.
11. Disconnect the ribbon cable from the connector
CN-G.
12. Remove three (3) screws holding the control unit to
the key fixing plate.
13. Now, the control unit is free.
REINSTALLATION
1. Remove remaining adhesive on the control panel
frame surfaces with a soft cloth soaked in alcohol.
2. Tear the backing paper from the new membrane
switch.
3. Insert the ribbon cable of the membrane switch into
the slit of the control panel frame and key fixing
frame.
4. Adjust the upper edge and right edge of the membrane switch to the small depression on the surface
of the control panel frame.
5. Attach the membrane switch to the control panel
frame by rubbing with a soft cloth not to scratch.
6. Tear the backing paper from the new graphic sheet.
7. Adjust the upper edge and right edge of the graphic
sheet to the large depression on the surface of the
control panel frame.
8. Attach the graphic sheet to the control panel frame
by rubbing with a soft cloth not to scratch.
9. Reconnect the ribbon cable to the connector CN-G.
10. Reconnect all leads and connectors removed from
the control unit
11. Reinstall the control panel assembly to the oven.
Control Unit
Graphic Sheet And Membrane Switch
Replacement
REMOVAL
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the control panel assembly, referring
to chapter of CONTROL PANEL ASSEMBLY AND
CONTROL UNIT REMOVAL.
5. Disconnect the ribbon cable from connector CN-G.
6. Tear away graphic sheet from control panel frame.
7. Tear away membrane switch from control panel
frame.
4-10
Ribbon Cable
Slit
Key Fixing Frame
Control Panel
FPC (Membrane Switch)
Key Sheet (Membrane Switch)
Figure 4-7. Key Unit Location
Section 4 Component Teardown
Door Sensing Switch, Secondary Interlock
Switch And Monitor Switch Removal
Door Sensing Switch, Secondary Interlock
Switch, And Monitor Switch Adjustment
Removal
1. Disconnect the power supply cord and remove the
oven from wall and remove outer case. (Refer to
procedure of “Removal of Oven from Wall” and
“Outer case Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
1. Disconnect the power supply cord and remove the
oven from wall and remove outer case. (Refer to
procedure of “Removal of Oven from Wall” and
“Outer case Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the control panel assembly, referring to
the procedure of “CONTROL PANEL ASSEMBLY,
CONTROL UNIT AND KEY UNIT REMOVAL”.
5. Remove the two (2) screws holding the latch hook to
the oven cavity front flange.
6. Remove the latch hook from the oven cavity front
flange.
7. Disconnect the wire leads of each switch.
8. Remove each switch from the latch hook by pushing
the one (1) stopper tub holding each switch.
9. Now, each switch is free.
Reinstall
1. Re-install each switch in its place. The secondary
interlock switch is in the lower position, door
sensing switch is in the upper position and the
monitor switch is in the middle position.
2. Re-connect wire leads to each switch. Refer to
pictorial diagram.
3. Secure the latch hook with two (2) mounting screws
to oven cavity front flange.
4. Make sure that the monitor switch is operating
properly and check continuity of the monitor circuit.
Refer to section 3 “Test Procedure” and “Adjustment
procedure”.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the control panel assembly, referring to
the procedure of “CONTROL PANEL ASSEMBLY,
CONTROL UNIT AND KEY UNIT REMOVAL”.
If door sensing switch, primary interlock switch and
monitor switch do not operate properly due to a misadjustment, the following adjustment should be made.
5. Loosen the two (2) screws holding latch hook to the
oven cavity front flange.
6 With door closed, adjust latch hook by moving it
back and forth, and up and down. In and out play
of the door allowed by the upper and lower position
of the latch hook should be less than 0.5mm. The
vertical position of latch hook should be adjusted so
that the door sensing switch and primary interlock
switch are activated with the door closed. The
horizontal position of the latch hook should be
adjusted so that the monitor switch is activated with
the door closed.
7. Secure the screws with washers firmly.
8. Check all of the switches operation. If any switch
has not activated with the door closed, loosen screw
and adjust the latch hook position.
4-11
Section 4 Component Teardown
After adjustment, check the following.
Door Replacement
1. In and out play of door remains less than 0.5mm
when in the latched position. First check upper
position of latch hook, pushing and pulling upper
portion of door toward the oven face. Then check
lower portion of latch hook, pushing and pulling
lower portion of the door toward the oven face.
Both results (play in the door) should be less than
0.5mm.
2. The door sensing switch, and primary interlock
switch interrupt the circuit before the door can be
opened.
3. Monitor switch contacts close when door is opened.
4. The contact of door sensing switch and primary
interlock switch open within 1.2mm gap between
right side of cavity face plate and door when door is
open.
5. Re-install outer case and check for microwave
leakage around door with an approved microwave
survey meter. (Refer to Microwave Measurement
Procedure.)
Removal
Latch
Hook
Latch
Heads
Door
Stop
Switch
(Door Sensing
Switch)
Monitor
Switch
Primary
Interlock
Switch
Figure 4-8. Latch Switch Adjustments
4-12
1. Disconnect the power supply cord and remove the
oven from wall and remove outer case. (Refer to
procedure of “Removal of Oven from Wall” and
“Outer case Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the hood exhaust louver from the oven
cavity by pushing the right and left tabs of the hood
exhaust louver. (Refer to the procedure of “HOOD
EXHAUST LOUVER REMOVAL”.)
5. Insert a putty knife (thickness of about 0.5mm) into
the gap A between the door stopper and the choke
cover as shown in Figure 4-10 to free engaging
parts.
6. Lift up the door stopper.
7. Now, the door stopper is free from door assembly.
8. Lift up the door assembly to release the upper and
lower door hinge pins from the upper and lower
oven hinges.
9. Now, the door assembly is free.
NOTE
When the individual parts are replaced, refer to “Door
Disassembly”.
Reinstall
1. On re-installing door, insert the lower oven hinge to
lower door hinge pin.
2. Insert upper oven hinge to the upper door hinge pin.
3. Shut the door (close contacts of interlock switches).
4. Make sure upper and lower oven hinges are inserted
into the upper an lower door hinge pins.
5. Make sure the door is parallel with oven face lines
(left and upper side lines) and door latch heads pass
through latch holes correctly.
6. Re-install the door stopper to the door assembly.
7. Re-install the hood exhaust louver to the oven cavity
front face plate.
Section 4 Component Teardown
Door Disassembly
NOTE
After any service to the door:
1. Make sure that door sensing switch and primary
interlock switch are operating properly. (Refer to
section 3 “Test Procedures”.).
2. An approved microwave survey meter should be
used to assure compliance with proper microwave
radiation emission limitation standards.
After any servicing, make sure of the following:
1. Door latch heads smoothly catch latch hook through
latch holes and that latch head goes through center
of latch hole.
2. Deviation of door alignment from horizontal line of
cavity face plate is to be less than 1.0mm.
3. Door is positioned with its face pressed toward
cavity face plate.
4. Re-install outer case and check for microwave
leakage around door with an approved microwave
survey meter. (Refer to Microwave Measurement
Procedure.)
NOTE
The door on a microwave oven is designed to act as an
electronic seal preventing leakage of microwave energy
from oven cavity during cook cycle. This function
does not require that door be air-tight, moisture-tight
or light-tight. Therefore, occasional appearance of
moisture, light or sensing of gentle warm air movement
around oven door is not abnormal and does not indicate a leakage of microwave energy from oven cavity.
Hood Exhaust
Louver
Upper Door
Hinge Pin
Upper
Oven
Hinge
Re-install
Removal
1. Disconnect the power supply cord and remove the
oven from wall and remove outer case. (Refer to
procedure of “Removal of Oven from Wall” and
“Outer case Removal”)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
NOTE
To discharge the high voltage capacitor, wait for 60
seconds and then short-circuit the connection of the
high-voltage capacitor (that is the connecting lead of
the high-voltage rectifier) against the chassis with the
use of an insulated screwdriver.
4. Remove the hood exhaust louver from the oven
cavity. (Refer to the procedure of “HOOD EXHAUST
LOUVER REMOVAL”.)
5. Remove door assembly, refer to “Door
Replacement”. Replacement of door components
are as follows:
6. Place door assembly on a soft cloth with latches
facing up.
NOTE
As engaging part of choke cover and door frame are
provided at 15 places, do not force any particular part.
Choke Cover
8. Insert a putty knife (thickness of about 0.5mm)
into the gap A between the choke cover and door
stopper and between the choke cover and the door
frame as shown Figure 4-10 to free engaging parts.
9. Pry the choke cover by inserting a putty knife in
order shown in Figure 4-10
10. Now choke cover is free from door panel and door
frame.
Door Assembly
Door Frame Assembly
Lower
Oven
Hinge
Latch Heads
Lower Door
Hinge Pin
Door Stopper
Re-install
Figure 4-9. Door Components
11. Remove two (2) screws holding the door panel to
the door frame assembly.
12. Release door panel from the door frame assembly.
NOTE
It is easier to release the engaging parts of the upper
or lower door hinge pin side at first.
4-13
Section 4 Component Teardown
Latch Spring, Latch Head And Door Panel
14. Release the latch spring from the tab of the latch
head and tab of the door panel.
15. Release the latch head from the door panel.
16. Now, the latch spring, latch head and door panel are
free.
A
Door Stopper
Choke Cover
Putty Knife
Door Frame
Figure 4-10. Door Disassembly
Door Glass For FGMV173KW/KB/KQ And
FGMV174KM
17. Remove one (1) screw holding the glass stopper to
the door frame.
18. Remove the glass stopper from the door frame.
19. Remove the door glass cap from the door frame.
20. Slide the door glass upwards.
21. Remove the door glass from the door frame by
sliding it to the right.
22. Now, the door glass is free.
NOTE
The door glass can not be exchanged for model
DGMV174KF and FGMV174KF.
Door Handle
23. Remove the one (1) screw holding the screw cap to
the door frame.
24. Remove the screw cap.
25. Remove the two (2) screws holding the door handle
to the door frame.
26. Now, the door handle is free.
4-14
Section 5 Wiring Diagrams
Wiring Schematic Oven OFF Condition
120V AC
60Hz
NOTE: "
" indicates components with potential above 250V
SCHEMATIC
BLK
WHT
RED
BLK
RED
GRN
G ND
L
N
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. CLOCK APPEARS ON DISPLAY
FUS E 20A
R E S ISTOR 470 k ohm 1/2W
NOTE S :
NOIS E FILTE R
1. C ircuits subject to change without notice.
2. Terminal with projecttion or opposite blue mark on lamp socket must
be connected to neutral wire.
3. Only certain models use the absolute humidity sensor.
4. P ower Transformer (Start Lead) terminal must be connected to hot
wire (R E D)
LINE C R OS S C APAC ITOR 1.0 uF 275V
NOIS E S UP R E S S ION C OIL
LINE BYPAS S C APAC ITOR
0.0033uF 250V
LINE BYPAS S C APAC ITOR
0.0033uF 250V
RED
G ND
2
4
6
WHT
A5
B1
YLW
C5
B3
BLK
High
Low
RY5
HL
WHT
BLU
C OM
BLK
N.O
P R I MAR Y
INTE R LOC K
S WITC H
WHT
WHT
FANM
OTOR
C1
TUR NTABLE
MOTOR
R E LAY
E2
BLU
G RY
S TIR R E R
MOTOR
RY7
E1
YLW
YLW
YLW
GRN
BLK
F3
F2
1F
S TOP
S WITC H
N.C .
HUMIDITY
S E NS OR
GRN GRN
GRN
LE AD WIR E C OLOR C ODE
C OM
MONITOR
S WITC H
WHT
BLK
RED
BLK
C OM
OVE N
LAMP
R E LAY
RY2
S E C ONDR Y
INTE R LOC K
R E LAYA
C OM.
WHT
N.O.
N.O.
RY1
C3
G RY
WHT
LVT
WHT
BLU
BLU
RED
OR G
OVE N
LAMP
A7
HOOD
LAMP
RY6
A9
HL
G RY
BLU
PPL
RED
TUR NTABLE
MOTOR
C ONTR OL UNIT
RY4
A3
N.C .
HOOD
C APAC ITOR
A1
RY3
G RY
WHT
RED
3
5
YLW
MG .
TE MP. FUS E
1
RED
OVE N THE R MAL
C UT OUT
BLK
BLK
BLU
HOOD FAN
THE R MAL
C UT OUT
HOOD
MOTOR
WHT
G RY
RED
BLK
HIG H
VOLTAG E
R E C TIFIE R
HIG H
VOLTAG E
C APAC ITOR
0.94uF
P OWE R
TR ANS FOR ME R
WHT
WHT
YLW
YLW
BLK
BR N
OR G
P NK
PPL
RED
:
:
:
:
:
:
BLAC K
BR OWN
OR ANG E
P INK
P UR P LE
RED
GRY
WHT
BLU
GRN
YLW
:
:
:
:
:
G R AY
WHITE
BLUE
GREEN
YE LLOW
BLK
YLW
MAG NE TR ON
5-1
C N-F
N.O.
5
3
C N-B
C N-C
1
C OM.
1
9
C N-A
T1
R Y2:
S E C ONDAR Y
R Y2 INTE R LOC K
R E LAY
(P OWE R UNIT)
C N-E
R Y1
BLK
WHT
BLK
RED
RED
C ONTR OL UNIT
N.O.
RED
LOAD
source
C OM.
BLK
GRY
WHT
WHT
GRY
C N-G
WHT
1
2
5-2
NOIS E FILTE R
to C hassis
S upport Right
1
C N-A
9 PPL
8
7 OR G
6
5 BLK
4
3 YLW
2
1 RED
C N-B
3 WHT
2
1 YLW
C N-C
5 BLK
4
3 WHT
2
1 RED
RED
RED
GRN
GRN
N.C .
P R IMAR Y
INTE R LOC K
C OM.
S WITC H
MONITOR
S WITC H
WHT
N.O.
BLK
GRN
N.O.
C OM.
YLW
YLW
RED
BLK
MAG NE TR ON
TE MP .
FUS E
DOOR S E NS ING S WITC H
C OM.
AH S E NS OR
to oven face plate
C N-E
1 BLK
2 GRN
to C hassis
S upport Right
C N-F
1 BLK
2 RED
3 WHT
TUR NTABLE
MOTOR
BLU
BLU
RED
YLW
YLW
GRY
FAN
MOTOR
HOOD LAMP
& S OC KE T
HOOD FAN MOTOR
RED
C AVITY
THE R MAL
C UT-OUT
BLU
BLK
RED 5 RED
YLW 4 YLW
WHT 3 WHT
BLK 2 BLK
BLU 1 BLU
6
BLK
3 BLK
GRY
WHT
WHT
Blue Marking
PPL
WHT
BLU
WHT
BLK
Blue
Marking
P ower S upply
C ord 120V 60Hz
OR G
BLU
WHT
P OWE R
TR ANS FOR ME R
R TR N-A 779
YLW
RED
BLK
P OWE R
TR ANS FOR ME R
R TR N-A 765
HIG H
VOLTAG E
C AP AC ITOR
HIG H
VOLTAG E
R E C TIFIE R
HOOD FAN
THE R MAL
C UT-OUT
WHT
WHT
YLW
BLK
MAG NE TR ON
HIG H VOLTAG E C OMP ONE NTS
YLW
BLK
WHT
WHT
YLW
S TIR R E R MOTOR
OVE N LAMP & S OC KE T
WHT 2 WHT
GRN 1 GRN
Section 5 Wiring Diagrams
Wiring Diagram
A3
A1
C OM
NO
A7
A9
A5
B1
B3
C5
C1
C OM
NO
C3
RY3
G 5S -124V
RY7
G 5N-1A24V
7.0uF / 230V
C 100
DU24D1-1P (M)R
RY2
RY6
G 5N-1A24V
RY5
G 5N-1A24V
RY4
G 5N-1A24V
T1
S10K300E
DU24D1-1P (M)R
RY1
C1
+
(C 50)
Q21
KR C 243M
MG Th
27
R4
D10 D11
10uF/35V
-
C 21
0.1uF/50V
C2
Q1
2S B1238
2702W
Q5 KIA79L05P
C5
DOOR S W.
D41
3301W
R 90
LD1-LD5 :LTS T-C 190KG KT
(YE LLOW G R E E N C OLOR )
LD5 LD4 LD3 LD2 LD1
R1
Q2
KTA1267Y
AHS E NS OR
F1
(J1)
1000uF/35V
R3
F3
-
INVE RTE R
-
34
45
50
49
42
48
41
38
39
40
36
46
47
44
35
43
32
37
R6
3.32KD
R 91
C 12
470
(R 20)
Q21
0.1uF
50V
4.7K
P 53
P 52
DTC 143E KA
(Q22)
Q28
DTA143E KA
DTA143E KA
0.1uF/50V
C 20
Q27
DTA143E KA
Q23
DTA143E KA
Q26
DTA143E KA
Q25
DTA143E KA
Q24
DTA143E KA
Q30
DTA143E KA
P 54
Q11
DTA143E KA
150KF
+
300K
D90
ZD10
10K
R 94
KDS 181
HZU3.6B2
15K
R 41
P 50
C 14
R 95
47K
R 97
47K
R 72 ~ R 76 : 270K x 5
C 60 ~ C 64 : 330pF / 50V x 5
R 76
R 75
R 74
R 73
R 72
C 64
C 63
C 62
C 61
C 60
47K
(R 50)
P 51
R 99
+
1K
+
3.3K
-
F2
2.4K
E2
C3
H3
D2
T2
D21
D27
D23
D24
D25
D26
D22
D4
SP1
15K
0.1uF / 50V
0.1uF/50V
C 10
R 30
R 96
R 102
8
PA154DR
D40
E1
R 101
3.57KD
C 90
37.4KF
R 12
0.1uF / 50V
C 91
75KF
10uF/35V
H1
C 13
R 100
(R 51)
R 93
R 92
R 40
360KF
4.7K
R 77
R 11
R 69
3
R 68
1.8KF
620K
R 71
R 98
C 40
R 70
15K
C 93
15K x5
Q10
DTA123E KA
C 92
G1
G2
G3
G4
C N-G
51 G 13
1
62
61
60
R 16
4.7K
10K
R 17
15K
timer
On-off
turn table
on-off
user
pref
G5
59
R 67
33
0.1uF/50V
C F1 4MHz
C 11
sensor
cook
sensor
reheat
auto
cook
G6
58
R 66
R 13
R 14
R 15
4.7K
4.7K
4.7K
15K
ZD1
HZ16-1
15K
chicken
nuggets
snack
menu
auto
defrost
G7
57
R 65
VR S 1
D1~D4:1N4002x4
D1
LC D
15K
56
R 64
pop
corn
baked
potato
vegetables
G8
1
2
3
G9
55
BAS E
IC -1
R 63
5 D3
15K
T1
15K
4
5
6
G 10
54
R 62
1
R 61
53
15K
7
8
9
15K
enter
+30 sec
S TART
0
S TOP
clear
power
level
G 12
52
R 60
KE Y UNIT
G 11
(NE G ATIVE )
Section 5 Wiring Diagrams
Control Wiring Schematic
5-3
47uF/16V
Section 5 Wiring Diagrams
Printed Wiring Board
LD1
5-4
LD2
LD3
LD4
LD5
Section 6 Parts List
Control Panel Parts
NO.
30
31
31-1
31-2
31-3
31-4
31-5
32
DESCRIPTION
CONTROL PANEL PARTS AND MISCELLANEOUS
Control unit
Panel sub. assembly
Key sheet (Graphic sheet)
FPC (Membrane switch)
Control panel [FGMV173KW] See Note 1.
Key fixing angle
Screw :3mm x 8mm
Screw :3mm x 8mm
76
Installation material assembly
77
Grommet
78
Toggle screw
79
screw :5mm x 85mm
80
screw :4mm x 8mm
81
screw :5mm x 35mm
82
Washer
89
Main harness
95
Rack
Note 1: If the control panel (31-3) is exchanged, the key sheet (31-1) and
FPC (31-2) must be exchanged at the same time.
CONTROL PANEL AND MISCELLANEOUS PARTS
30
31-5
32
77
31-5
76
31
79
80
78
81
82
89
88
31-1
31-4
31-3
95
31-2
6-1
Section 6 Parts List
Oven And Cabinet Parts
27
97
36
101
96
12
48
16
97
20
97
54
97
45
21
97
104
47
46
98
13
10
97
83
50
28
52
14
15
11
104
102
99
96
90
22
4
17
97
99
99
83
42
116
9
55
53
61
92
62
55
116
91
99
7
100
18
8
49
106
9
106
41
29
108
44
99
51
3
93
83
38
94
39
83
43
40
2
8
6
50
102
1
5
19
26
97
37
97
11
93
25
14
23
105
24
105
105
115
6-2
Section 6 Parts List
NOTE: Parts marked "*" may cause undue microwave exposure. Parts marked "∆" are used in voltage more than 250V.
NO.
DESCRIPTION
ELECTRIC PARTS
∆ 1
∆ 2
3
4
5
∆ 6
*∆ 7
8
9
10
11
12
13
14
15
16
17
High voltage rectifier
High voltage capacitor
Turntable motor
Stirrer motor
Thermal cut out 60C (Hood Fan)
Power transformer
Magnetron
Pri. Interlock and door sensing switches
Monitor switch (V-5220Q) and fuse assembly (20A 250 VAC) or
Monitor switch (D3V -1G -2C25) and fuse assembly (20A 250 VAC Interchangeable)
Power supply cord
Oven lamp socket
Hood fan motor
Fan motor
Oven lamp
Thermal cut -out 145ºC (Cavity)
AH sensor (Humidity sensor)
Temperature fuse 150ºC (Magnetron) or Thermal cut out 145ºC (Magnetron)
CABINET PARTS
18
19
20
21
22
23
24
25
26
27
28
29
Hood exhaust louver [FGMV173K]
Right base plate
Rear stay
Outer case cabinet [FGMV173K]
Schematic diagram
Hood lamp glass assembly [FGMV173K]
Hood lamp glass angle [FGMV173K]
Hood lamp glass
Base cover [FGMV173K]
Cushion
Rubber cushion
Mag cushion
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Exhaust damper assemply
Turntable support assembly
Turntable tray
Capacitor holder
Stirrer cover assembly
Stirrer fan assembly
Noise filter unit
Turntable motor packing
Latch hook
Unit mounting plate
Fan blade
Cord bushing
Oven lamp cover
Hood intake duct R
Hood intake duct cushion
Lamp filter
Chassis support left
OVEN PARTS
6-3
Section 6 Parts List
NO.
DESCRIPTION
53
54
55
61
62
90
91
92
93
94
108
115
117
Chassis support right
Hood duct
Rack Holder
Left rack holder
Right rack holder
DHHS/GRD/caution label
Monitor caution lael
Charcoal filter
Grease filter
Canoe clip
Cushion
Deflector
Menu label [DGMV174KF]
SCREWS, NUTS, WASHERS AND MISC.
Screw : 4mm x 8mm
Sensor grd wire
Screw : 4mm x 8mm
Screw : 4mm x 12mm
Screw : 4mm x 8mm
Special screw
Special screw
Screw : 3mm x 6mm
Screw : 4mm x 12mm
Screw : 4mm x 8mm
DHHS caution
Screw : 3mm x 8mm
83
96
97
98
99
100
101
102
104
105
106
116
6-4
Section 6 Parts List
Door Parts for FGMV185KB/W
DESCRIPTION
REF. NO.
DOOR PARTS FOR FGMV185KB/W
56
64
65
68
69
71
72
73
100
101
118
200
201
202
Door stopper
Door sub assembly [FGMV185KW] [FGMV185KB]
Door frame [FGMV185KW] [FGMV185KB]
Latch head
Spring
Choke cover
Sealer film
Door handle [FGMV185KW] [FGMV185KB]
Screw : 4mm x 10mm
Screw : 4mm x 15mm
Screw : 4mm x 8mm
Door glass [FGMV185KW] [FGMV185KB]
Glass stopper [FGMV185KW] [FGMV185KB]
Badge [FGMV185KW] [FGMV185KB]
56
71
100
72
118
65
201
100
100
68
69
202
202
200
101
73
6-5
Section 6 Parts List
Packing And Accessories
DESCRIPTION
REF. NO.
PACKING AND ACCESSORIES
36
38
76
82
84
85
86
87
93
95
Damper assembly
Turntable
Accessory assembly
Cushion
Installation instructions
Instruction book
Top template
Top template
Mesh filter
Rack
TOP P AD
DOOR P R OTE C TOR
P R OTE C TION S HE E T
WR AP C OVE R
38
TUR NTABLE TR AY
C ABINE T C OVE R
TR AY P AD
82
C US HION
DOOR P AD
76
AC C E S S OR Y AS S E MBLY
87
WALL TE MP LATE
84
INS TALLATION INS TR UC TION
86
TOP TE MP LATE
95
85
R AC K
OP E R ATION MANUAL
R AC K P AD
93
G R E AS E FILTE R (x2)
36
DAMP E R AS S E MBLY
BOTTOM P AD
AC C E S S OR Y HOLDE R
E HP LABE L
Non-replaceable items
P AC KING C AS E
6-6
Download PDF