Electrolux EI30MO45GSA Service manual

Technical Service Manual
Microwave Oven
GRAIN DIRECTION
(ALL PARTS)
Models
EI27MO45GSA
EI30MO45GSA
Publication #5995534665
P/N 316439275
April 2009
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
Basic Information
This Manual has been prepared to provide Electrolux Service Personnel with Operation and
Service Information for Electrolux Microwave Ovens EI27MO45GSA and EI30MO45GSA.
Table of Contents
Section 1 Basic Information
Section 3 Troubleshooting and Testing
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
Oven Diagram ......................................................... 1-10
Warnings and Cautions ........................................... 3-1
Troubleshooting Guide Chart .................................. 3-2
Test Procedures ...................................................... 3-3
Circuit Testing Charts .............................................. 3-12
Section 2 Operation
Operating Sequence Description.............................
Off Condition ........................................................
Cooking Condition ................................................
Oven Schematic-Off Condition ................................
Oven Schematic-Cooking Condition........................
Variable Cooking .....................................................
Sensor Cooking Condition....................................
Cooking Sequence ...............................................
Touch Control Panel Assembly ...............................
Component Descriptions .........................................
Door Open Mechanism ........................................
Primary Switch, Third Door Switch & Door
Sensing Switch .....................................................
Monitor Switch ......................................................
Cooling Fan Motor ................................................
Turntable Motor ....................................................
Monitor Fuse ........................................................
Cavity Temperature Fuse .....................................
C/T Temperature Fuse .........................................
Humidity Sensor Circuit ...........................................
2-1
2-1
2-1
2-2
2-2
2-3
2-3
2-3
2-4
2-4
2-4
2-4
2-5
2-5
2-5
2-5
2-5
2-5
2-6
Section 4 Component Teardown
Warnings and Cautions ........................................... 4-1
Outer Case Removal ............................................... 4-2
Power Transformer Removal................................... 4-2
High Voltage Rectifier and High
Voltage Capacitor Removal ..................................... 4-3
Magnetron Removal ................................................ 4-3
Oven Lamp and Lamp Socket Removal .................. 4-4
Positive Lock® Connector
(No-Case Type) Removal ........................................ 4-4
Fan Motor Removal ................................................. 4-5
Servicing The Touch Control Panel ......................... 4-6
Control Panel Assembly Removal ........................... 4-7
Key Sheet Replacement .......................................... 4-7
Door Sensing Switch/Primary Switch/Third Door
Switch And Monitor Switch Replacement ................ 4-8
Door Sensing Switch/Primary Switch/Third Door
Switch And Monitor Switch Adjustment ................... 4-8
Door Replacement................................................... 4-9
Sealer Film .............................................................. 4-10
Turntable Motor Removal ........................................ 4-10
Section 5 Wire Diagrams
Wiring Schematic Oven Off Condition .....................
Pictorial Diagram .....................................................
Wiring Diagram ........................................................
5-1
5-2
5-3
Section 6 Parts List
Parts Listing .............................................................
Oven And Cabinet Parts Exploded View .................
Control And Door Parts Exploded View...................
Packing and Accessories Exploded View................
1-2
6-1
6-3
6-4
6-5
Basic Information
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., AND 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.
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.
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
Basic Information
Precautions To Be Observed Before And During Servicing To Avoid
Possible Exposure To Excessive Microwave Energy
(a) Do not operate or allow the oven to be operated with the door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave
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.
(c) 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.
(d) 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.
(e) 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
Basic Information
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.
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.
Don't Touch !
Danger High Voltage
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.
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:
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.
2.
3.
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.
4.
5.
6.
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
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°±5C (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
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°±5C (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 the 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
Basic Information
Product Specification
Item
Description
Power Requirements
(USA)120 Volts / 13.0 Amperes / 1500 Watt
60 Hertz
Single phase, 3 wire grounded
Power Output
1100 watts (IEC 705 Test Procedure)
Operating frequency of 2450MHz
Case Dimensions
Width 24-5/8’”
Height 14”
Depth 19-5/16”
HSS Unit Dimensions (including handle)
Width 30”
Height 20-7/8”
Depth 22-7/8”
Cooking Cavity Dimensions
(2.0 Cubic Feet )
Width 17-3/8”
Height 10-1/2”
Depth 18-5/8”
Oven Cavity Light
40 Watt
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
Tray Size 15-9/16
Sensor modes pads, Auto cook pads, Timer on-off pad, Set clock pad,
User Pref pad, Quick start pad, Number selection pads, Power Level pad,
Add 30 sec pad, Stop/Clear pad, Keep warm pad, and Start pad.
Safety Standard
UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J
Canadian Standards Association
Health CANADA, Industry Canada
Weight
Approx. 55 lbs.
1-8
Basic Information
Grounding Instructions
3-Pronged Plug
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.
Grounded
Receptacle Box
Grounding Pin
3-Pronged Receptacle
IMPROPER USE OF THE GROUNDING PLUG CAN
RESULT IN A RISK OF ELECTRIC SHOCK.
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.
If an extension cord must be used, it should be a 3-wire,
15 amp. or more rated cord. Do not drape over a
countertop or table where it can be pulled on by children
or tripped over accidentally.
1-9
Basic Information
Touch Control Panel
Oven Diagram
1. One touch door open button. Push to open door.
2. Door latches. The oven will not operate unless the
door is securely closed.
3. Removable turntable support.
4. Removable turntable. The turntable will rotate clock
wise or counterclockwise.
5. Oven lamp. It will light when oven is operating or
door is opened.
6. Oven door with see-through window.
7. Ventilation openings. (Rear)
8. Auto-Touch control panel.
9. Time display: Digital display, 99 minutes 99 seconds.
10. Wave guide cover.
11. Power supply cord.
7
11
5
6
9
2
10
8
1
4
Some one-touch cooking features uch as “add 30
sec” are disabled after three minutes when the oven
is not in use. These features are automatically
enabled when the door is opened and closed or the
STOP/ CLEAR pad is pressed.
3
1-10
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 and press clock”.
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 by touching the NUMBER
pads. Program the power level by touching the POWER
LEVEL pad and then a Number pad.
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 / Turntable Motor / Fan Motor
RY2
Power Transformer
6. When the door is opened during a cook cycle, the
monitor switch, door sensing switch, third door
switch, primary switch relay (RY1) and secondary
interlock relay are activated with the following results.
The circuits to the turntable motor, the cooling fan
motor, and the high voltage components are
de-energized, the oven lamp remains on, and the
digital read-out displays the time still remaining in the
cook cycle when the door was opened.
7. The monitor switch electrically monitors the
operation of the primary and third door switch and is
mechanically associated with the door so that it will
function in the following sequence.
(1) When the door opens from the closed position,
the secondary interlock relay (RY2) secondary
switch open their contacts. And contacts of the
relay (RY1) remains closed. 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 switch, third door 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 C/T fuse, primary interlock
switch, relay (RY1) and secondary interlock relay (RY2),
causing the C/T 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 2370 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
Operation
SCHEMATIC
NOTE: "*" indicates components with
potential above 250V.
ORG
OL
FM
TURNTABLE
MOTOR
GRY
WHT
TTM
OVEN
LAMP
FAN
MOTOR
POWER TRANSFORMER
DOOR
SENSING
SWITCH
COM.
N.O.
H
BLK
N.C.
MONITOR
SWITCH
B1
GRN
COM
N
GND
C1
RY1
OVEN
LAMP
RELAY
C3
GND
HUMIDITY
SENSOR
NOISE
FILTER
F2
WHT
WHT
GRY
N.O.
COM.
RY2
SECONDARY
INTERLOCK
RELAY
F1
CONTROL UNIT
HIGH
VOLTAGE
RECTIFIER
GRY
WHT
HIGH
VOLTAGE
CAPACITOR
F3
GRY
L
MAGNETRON
B2
C2
WHT
WHT
120 VAC
60Hz
YLW
BLU
THIRD
DOOR
SWITCH
COM.
N.O.
BRN
RED
BLK
RED
ORG
RED
PRIMARY
INTERLOCK
SWITCH
COM
N.O.
C/T FUSE
BRN
BLK
CAVITY TEMP
FUSE
WHT
NOTE: Condition Of Oven
1. Door Closed
2. Clock Appears On Display
Figure 2-1. Oven Off Condition
ORG
OL
FM
TURNTABLE
MOTOR
GRY
WHT
TTM
OVEN
LAMP
GRN
B1
GND
MAGNETRON
RY1
OVEN
LAMP
RELAY
GND
HUMIDITY
SENSOR
WHT
NOISE FILTER
F2
COM.
RY2
SECONDARY
INTERLOCK
RELAY
CONTROL UNIT
F1
GRY
WHT
WHT
GRY
N.O.
HIGH
VOLTAGE
CAPACITOR
F3
Figure 2-2. Oven ON (Cooking) Condition
2-2
GRY
C3
WHT
WHT
C1
MONITOR
SWITCH
B2
C2
L
N.C.
COM
N
120 VAC
60Hz
FAN
MOTOR
POWER TRANSFORMER
DOOR
SENSING
SWITCH
COM.
N.O.
H
BLK
YLW
BLU
THIRD
DOOR
SWITCH
COM.
N.O.
BRN
RED
BLK
RED
ORG
RED
PRIMARY
INTERLOCK
SWITCH
COM
N.O.
C/T FUSE
BRN
BLK
CAVITY TEMP
FUSE
WHT
1.
2.
3.
4.
SCHEMATIC
NOTE: Condition Of Oven
Door Closed
Cooking Time Programmed
Variable Cooking Control "High"
"Start" Pad Touched
HIGH
VOLTAGE
RECTIFIER
Operation
2. Heat Potatoes. Moisture and humidity is emitted
rapidly. You can smell the aroma as it cooks.
Variable Cooking
When Variable Cooking Power is programmed, 120 volts
AC is supplied to the power transformer intermittently
through the contacts of relay (RY-2) and is operated by
the control unit within a 32 second time base. Microwave
power operation is as follows:
Vari-Mode
ON TIME
OFF TIME
Power 10 (High) (100% Power)
Power 9 (P-90) (Approx. 90%)
Power 8 (P-80) (Approx. 80%)
Power 7 (P-70) (Approx. 70%)
Power 6 (P-60) (Approx. 60%)
Power 5 (P-50) (Approx. 50%)
Power 4 (P-40) (Approx. 40%)
Power 3 (P-30) (Approx. 30%)
Power 2 (P-20) (Approx. 20%)
Power 1 (P-10) (Approx. 10%)
Power 0 (P-0) (0% 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.
MIC
RO
WA
VE
3. Sensor detects moisture and humidity and
calculates cooking time and variable power.
AH SENSOR
MIC
RO
WA
VE
COOKING SEQUENCE
The ON/OFF time ratio does not correspond with
the percentage of microwave power, because
approx. 2 seconds are needed for heating of the
magnetron filament.
1. Touch SENSOR COOK pad.
NOTE: The oven should not be operated on SENSOR
immediately after plugging in the unit. Wait two minutes
before cooking on SENSOR.
SENSOR COOKING CONDITION
Using the SENSOR COOK 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.
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
experiment 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.
2. Select desired Sensor setting.
3. Touch START pad.
The coil of shut-off relay (RY1, RY6) is energized, the
oven lamp and cooling fan motor are turned on, but
the power transformer is not turned on.
4. After about 16 seconds, the cook relay (RY2) is
energized. The power transformer is turned on,
microwave energy is produced and first stage is
started. The 16 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 STOP/CLEAR pad.
5. 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, turn, or
season food.
6. When the timer reaches zero, an audible signal
sounds. The shut-off relay and cook relay are
de-energized and the power transformer, oven lamp,
etc. are turned off.
7. 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.
2-3
Operation
Touch Control Panel Assembly
Component Descriptions
The touch control section consists of the following units.
1. Key Unit
2. Control Unit (Consists of Power Unit and LSI Unit).
DOOR OPEN MECHANISM
The door is opened by pushing the open button on the
control panel, refer to the Figure D-1. When the open
button is pushed, the open button pushes up the switch
lever, and then the switch lever pushes up the latch head.
The latch heads are moved
upward and released from latch hook. Now the door will
open.
The principal functions of these units and the signals
communicated among them are explained below.
Key Unit
The key unit is composed of a matrix, signals generated
in the LSI are sent to the key unit through P53 ~ P57 &
P80 ~ 87. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI
through P53 ~ P57 to perform the requested function.
Latch Heads
Control Unit
Door
Control unit consists of LSI, reset circuit, indicator circuit,
power source circuit, relay circuit, buzzer circuit,
synchronizing signal circuit and back light circuit.
1. Reset Circuit
This circuit generates a signal which resets the LSI to
the initial state when power is supplied.
2. Indicator Circuit
This circuit consists of VFD (Vacuum Fluorescent
Display).
3. Power Source Circuit
This circuit generates voltages necessary in 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
VSS
-5V
LSI(IC1)
4. Relay Circuit
A circuit to drive the magnetron, fan motor, turntable
motor and light the oven lamp.
5. Buzzer Circuit
The buzzer is responsive to signals from the LSI to
emit audible sounds (key touch sound and
completion sound).
6. Synchronizing Signal Circuit
The power source synchronizing signal is available in
order to compose a basic standard time in the clock
circuit. It accompanies a very small error because it
works on commercial frequency.
7. Door Sensing Switch
A switch to “tell” the LSI if the door is open or closed.
8. Absolute Humidity Sensor Circuit
This circuit detects moisture of the cooking food to
allow its automatic cooking.
Door Sensing
Switch
Monitor Switch
Third Door
Switch
Switch Lever
Primary
Switch
Figure 2-5 . Door Open Mechanism
PRIMARY SWITCH, THIRD DOOR SWITCH & DOOR
SENSING SWITCH
The primary switch and third door switch mounted
parallel to each other horizontally in the lower positions
of the latch hook, the door sensing switch is mounted
horizontally in the upper position of the latch hook. They
are activated by the latch head on the door. When the
door is opened, the switches interrupt the power to all
high voltage components, except the oven lamp. A cook
cycle cannot take place until the door is firmly closed
thereby activating all interlock switches. The secondary
interlock system consists of the door sensing switch and
the secondary interlock relay located on the control circuit
board.
2-4
Operation
MONITOR SWITCH
TURNTABLE MOTOR
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 C/T fuse, when the contacts of
the secondary interlock relay (RY2) and primary interlock
switch fail to open when the door is opened.
The turntable motor rotates the turntable located on the
bottom of the oven cavity, so that foods on the turntable
cook evenly during cooking. The turntable may turn in
either direction.
MONITOR FUSE
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, primary switch and third door switch are in the
OFF condition (contacts open) due to their being
normally open contact switches.
2. As the door goes to a closed position, the monitor
switch contacts are first opened and then the door
sensing switch, primary switch and third door switch
contacts close. (On opening the door, each of these
switches operate inversely.)
3. If the door is opened, and the secondary interlock relay (RY2) and primary interlock switch contacts fail to
open, the C/T fuse blows simultaneously with closing
of the monitor switch contacts.
1. The monitor fuse blows when the contacts (COMNO) of the primary switch remain closed with the
oven door open and when the monitor switch closes.
2. If the wire harness or electrical components are
short-circuited, this monitor fuse blows to prevent an
electric shock or fire hazard.
CAVITY TEMPERATURE FUSE
The cavity temperature fuse located on the top of the
oven cavity, is designed to prevent damage to the oven
by fire. If the food load is overcooked, by either error in
cook time or defect in the control unit, the cavity temperature fuse will open. Under normal operation, the cavity
temperature fuse remains closed. However, when
abnormally high temperatures are reached within the
oven cavity, the cavity temperature fuse will open at
302°F (150°C) causing the oven to shut down.
Before replacing a blown C/T fuse, test the door
sensing switch, secondary interlock relay (RY2),
relay (RY1), primary/third door interlock switch and
monitor switch for proper operation. (Refer to
Section 3 “Test procedure”).
NOTE: The fuse must be replaced, it does not reset.
C/T TEMPERATURE FUSE
C/T fuse and monitor switch are replaced as an
assembly.
COOLING FAN MOTOR
The cooling fan motor drives a blade which draws in
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.
The C/T fuse, located near the magnetron, is designed to
prevent damage to the magnetron if an over heated
condition develops in the tube due to cooling fan failure,
obstructed air guide, dirty or blocked air intake, etc.
Under normal operation, the C/T fuse remains closed.
However, when abnormally high temperatures are
reached within the magnetron, the C/T fuse will open at
302°F (150°C) causing the oven to shut down.
1. The C/T fuse blows when the contacts (COM-NO) of
the secondary interlock relay (RY2) and primary
interlock switch remain closed with the oven door
open and when the monitor switch closes.
2. If the wire harness or electrical components are
short-circuited, this monitor fuse blows to prevent an
electric shock or fire hazard.
NOTE: The fuse must be replaced, it does not reset.
2-5
Operation
Humidity Sensor Circuit
(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.
Sensing Part
(Open vessel)
Ventilation
Openings
Sensing Part
(Closed vessel)
Sensing Part
Sensing Part
(Open vessel) (Closed vessel)
Thermistor
Thermistor
Element
Element
Sensor
Case
View of Sensor Case Removed
Cross Section View
Figure 2-6. Humidity Sensor
(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.
(3) Detector Circuit of Absolute Humidity Sensor
Circuit:
This detector circuit is used to detect the output
voltage of the absolute humidity circuit to allow the
LSI to control sensor cooking of the unit. When the
unit is set in the sensor cooking mode, 16 seconds
clearing cycle occurs first, then the detector circuit
starts to function and the LSI observes the initial
voltage available at its AN6 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 R50-1. Changing
the resistance values results in that there is the same
potential at both F-3 terminal of the absolute
humidity sensor and AN7 terminal of the LSI. The
voltage of AN6 terminal will indicate about -2.5V.
This initial balancing is set up about 16 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 of the bridge circuit is deviated to increase
the voltage available at AN6 terminal of the LSI.
Then the LSI observes that voltage at AN6 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
AN6 terminal 16 seconds after the unit has been put
in the Sensor Cooking mode, if it is not possible to
balance, of the bridge circuit due to disconnection of
the absolute humidity sensor, ERROR will appear on
the display and the cooking is stopped.
1) Humidity sensor circuit:
150k
Absolute humidity (g/m 2 )
75k
C. Thermistor in
closed vesssl
S. Thermistor in
open vessel
Figure 2-7. Humidity Sensor Operation
47k
11
F-1
C
F-3
3.57k
S
F-2
3.32k 1.8k
10
VA : -15V
2-6
64
5
63
6
62
7
61
8
60
3
5
37.4k
0.1
µF
R3
S : Thermistor
open vessel
C : Thermistor
closed vessel
300k
R51
S
620k
4
+
10k
360k
9
VA : -15V
SW2
P31
SW3
P32
SW4
P33
SW5
P34
AN7
LSI
(IC1)
2
47k
12
SW1
P30
0.01µF
R2
IC2(IZA495DR)
Absolute humidity vs,
output voltage characterist
0.01µF
Operational
amplifier
Output
voltage
+
0.015µF
R1
Output voltage
C
1
VC : -5V
6
AN6
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.
If the oven becomes inoperative because of a blown C/T fuse, check the monitor switch, relay (RY1)
secondary interlock relay (RY2), door sensing switch and primary interlock switch before replacing the
C/T fuse. If the C/T fuse is replaced, the monitor switch must also be replaced.
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.
6. After that procedure, reconnect the power supply cord.
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
Troubleshooting and Testing
CK = Check / RE = Replace
Home fuse or circuit breaker blows
when power cord is plugged into wall
receptacle
C/T fuse blows when power cord is
plugged into wall receptacle.
OFF
CONDITION
All letters and indicators do not ap pear in display when power cord is
first plugged into wall outlet.
Display does not operate properly
when STOP/CLEAR key is touched.
(Buzzer should sound and ":" or time
of day should appear in display.)
Oven lamp does not light when door
is opened.
Oven lamp does not go out when
door is closed.
Oven lamp lights but fan motor and
turntable motor do not operate.
Oven does not go into cook cycle
when START pad is touched
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.)
COOKING
CONDITION
Oven goes into a cook cycle but ex tremely uneven heating is produced
in oven load (food).
Oven does not cook properly when
programmed for Cooking Power P-50
mode. (Operates properly on Cooking
P-HI (HIGH) mode.)
Oven goes into COMPU DEFROST
but food is not defrosted well.
SENSOR
COOKING
CONDITION
AH sensor does not end during
sensor cooking condition. (Oven
does not shut off after a cup of
water is boiling by sensor cooking)
Oven stops at 16 sec. after starting.
3-2
O
NOISE FILTER
AH SENSOR
FOIL PATTERN ON PWB.
COMPU DEFROST
RELAY (RY1)
KEY UNIT
DIRTY OVEN CAVITY
LOW VOLTAGE
WRONG OPERATION
TOUCH CONTROL PANEL
TURNTABLE MOTOR
COOLING FAN MOTOR
OVEN LAMP OR SOCKET
MONITOR FUSE
MONITOR SWITCH
PRIMARY INTERLOCK SWITCH
SECONDARY INTERLOCK SYSTEM
MAGNETRON TEMP FUSE
CAVITY TEMPERATURE FUSE
HIGH VOLTAGE CAPACITOR
H.V. RECTIFIER ASSEMBLY
POWER TRANSFORMER
MAGNETRON
PROBLEM
SHORT OR OPENED WIRING
CONDITION
RE RE A B C D E E F F G H RE RE CK I CK CK CK J K L M N
SHORT IN POWER CORD
POSSIBLE CAUSE
AND
DEFECTIVE PARTS
TEST PROCEDURE
Troubleshooting and Testing
Test Procedures
Procedure
Letter
A
Component Test
MAGNETRON ASSEMBLY TEST
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.
The following test procedure should be carried out with the microwave oven in a fully assembled
condition (outer case fitted).
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 POWER 10(HIGH) 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 38 to 78°F (21 to 42.6°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
Troubleshooting and Testing
Procedure
Letter
B
Component Test
POWER TRANSFORMER TEST
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 coils with an ohmmeter. On the 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 90 ohms; 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.
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.
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.
NOTE: Be sure to use an ohmmeter that will supply a forward bias voltage of more than 6.3 volts.
3-4
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.
CAVITY TEMPERATURE FUSE 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)
A continuity check across the cavity temperature fuse terminals should indicate a closed circuit
unless the temperature of the cavity temperature fuse reaches approximately 302°F(150°C). An
open cavity temperature fuse indicates overheating of the oven, exchange the cavity
temperature fuse 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.
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.
C/T 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)
A continuity check across the C/T fuse terminals should indicate a closed circuit unless the
temperature of the C/T fuse reaches approximately 302°F (150°C). An open C/T fuse indicates
overheating of the magnetron. Check for restricted air flow to the magnetron, especially the
cooling fan air guide.
If temperature fuse indicates an open circuit at room temperature, replace fuse.
(continued next page)
3-5
Troubleshooting and Testing
Procedure
Letter
Component Test
5. If the C/T fuse is blown when the door is opened, check the secondary interlock relay, primary
interlock switch and monitor switch according to the “TEST PROCEDURE” for those switches
before replacing the blown monitor fuse.
Before replacing a blown CT fuse, test the secondary interlock relay, primary interlock
switch, door sensing switch and monitor switch for proper operation.
6.
7.
8.
9.
F
If the C/T fuse is blown by improper switch operation, the C/T fuse and monitor switch must
be replaced with “C/T fuse and monitor switch assembly”, even if the monitor switch operates
normally. The C/T fuse and monitor switch assembly is
comprised of a 20 ampere fuse and 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 AND THIRD DOOR 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)
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 third door
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.
SECONDARY INTERLOCK SYSTEM TEST DOOR SENSING 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.
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.
If the door sensing switch contacts fail in the open position and the door is closed, the
cooling fan, turntable and oven light will be activated by RY1.
3-6
Troubleshooting and Testing
Procedure
Letter
Component Test
SECONDARY INTERLOCK RELAY (RY2)
1.
2.
3.
4.
5.
6.
7.
8.
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.
Disconnect two (2) wire leads from the male tab terminals of the Secondary Interlock Relay.
Check the state of the relay contacts using a ohmmeter. The relay contacts should be open.
If the relay contacts are closed, replace the circuit board entirely or the relay itself.
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.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
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 primary switch is 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 the wire lead to the monitor switch (COM) terminal and
check the continuity of the 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.
Screwdriver
Red
WHT/WHT
Monitor
Switch
Primary
Interlock
Switch
Third Door
Switch
3-7
Ohmmeter
Troubleshooting and Testing
Procedure
Letter
I
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 also the Control Unit is divided into two units, LSI Unit
and Power Unit, and troubleshooting by unit replacement is described according to the symptoms
indicated.
Before testing,
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.
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.
1. Key Unit.
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.
Check Key unit ribbon connection before replacement.
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.
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.
4. Replace the Key unit.
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.
3-8
Troubleshooting and Testing
Procedure
Letter
Component Test
2. Control Unit
The following symptoms indicate a defective control unit. Before replacing the control unit, perform
the Key unit test (Procedure J) to determine if control unit is faulty.
2-1 In connection with pads.
1. When touching the pads, a certain group of pads do not produce a signal.
2. When touching the pads, no pads produce a signal.
2-2 In connection with indicators.
1. At a certain digit, all or some segments do not light up.
2. At a certain digit, brightness is low.
3. Only one indicator does not light.
4. The corresponding segments of all digits do not light up; or they continue to light up.
5. Wrong figure appears.
6. A certain group of indicators do not light up.
7. The figure of all digits flicker.
8. The following symptoms indicate a defective LSI unit.
• When touching the keys on the touch screen, a certain key produces no signal at all.
• When touching a number key on the touch screen, two figures or more are displayed.
• When touching the keys on the touch screen, sometimes a key produces no signal.
2-3 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. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Reconnect all leads removed from components during testing.
5. Re-install the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
J
KEY UNIT 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.
Isolate the key unit with the control panel frame to be tested.
Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit,
check the circuit between the pins of the key unit that correspond to the STOP/CLEAR pad.
When the pad is pressed, the ohmmeter should indicate short circuit. When the pad is released,
the ohmmeter should indicate open circuit. If incorrect readings are obtained, the key unit is
faulty and must be replaced. About the other pads, the above method may be used.
6. Reconnect all leads removed from components during testing.
7. Re-install the outer case (cabinet).
8. Reconnect the power supply cord after the outer case is installed.
9. Run the oven and check all functions.
(See illustration on next page)
3-9
Troubleshooting and Testing
Procedure
Letter
Component Test
Key Unit Test
Pin
NO. G1
Pin
NO. G13
Key unit ribbon cable
Key unit (Membrane Switch) front view
K
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.
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. 1 of the 2 pin connector (A) and the
common terminal of the relay RY1 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
RY1
RY2
8.
9.
10.
11.
12.
13.
14.
OPERATIONAL VOLTAGE
Approx. 12.0V D.C.
Approx. 11.0V D.C.
CONNECTED COMPONENTS
Oven lamp / Turntable motor / Cooling fan motor
Power transformer
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
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.
3-10
Troubleshooting and Testing
Procedure
Letter
L
Component Test
DEFROST TEST
WARNING : The oven should be fully assembled before following procedure.
1. Place one cup of water in the center of the turntable tray in the oven cavity.
2. Close the door.
3. Touch the “ DEFROST “ pad, then number 2.
4. The oven is in Defrost Center cooking condition.
5. The oven will operate as follows:
MENU
STEAKS/CHOPS/FISH
0.5lb
N
1ST STAGE
LEVEL
TIME
60%
57sec.
2ND STAGE
LEVEL TIME
40%
22sec.
NOISE FILTER 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.
Disconnect the leads to the primary of the power transformer.
Using an ohm-meter, check between the terminals as described in the following table:
NOISE FILTER UNIT
MONITOR
FUSE
NOISE SUPPRESSION COIL
LINE CROSS CAPACITOR
0.22uF/AC 250V
LINE BYPASS CAPACITOR
0.0033uF/AC125V
LINE BYPASS CAPACITOR
0.0033uF/AC125V
GRY
RED
MEASURING POINT
Between N and H
Between terminal N and GRY
INDICATION OF OHM-METER
Open Circuit
Between terminal H and RED
Short Circuit
Short Circuit
If incorrect readings are obtained, replace the noise filter.
6. Reconnect all leads removed from components during testing.
7. Re-install the outer case (cabinet).
8. Reconnect the power supply cord after the outer case is installed.
9. Run the oven and check all functions.
3-11
Troubleshooting and Testing
Pin# Signal
VSS
1
I/O
IN
2
XIN
IN
3
4
5
6
7
8
XOUT
TEST
VDD
P21
RXD
RESET
OUT
IN
IN
OUT
IN
IN
9
10
11
12
13
P20
P00
P01
P02
AVDD
OUT
OUT
OUT
OUT
IN
14
VREF
IN
15
P10
OUT
16
P11
OUT
17
18
P12
AJN3
OUT
IN
19
20
AJN4
AJN5
IN
IN
21
AJN6
IN
22
AVSS
IN
23
INTO
IN
24
25
26
27
28
29
P31
P32
P33
TXD
P36
P37
OUT
OUT
OUT
IN
OUT
OUT
Description
Power source voltage : -5.0 Volts.
The power source voltage to the drive LSI is input to VSS terminal.
Internal clock oscillation frequency control input setting.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect to XOUT terminal.
Internal clock oscillation output. Output to control oscillation input to XIN.
Terminal to input the program to LSI
Power source voltage : GND (0 Volts)
Not Used
Terminal to input the program to LSI.
Auto clear terminal. Signal is input to reset the LSI to the initial state when power is applied. Temporarily set to “L” level the moment power is applied, at this time the LSI is reset.
Thereafter set at “H” level.
Not Used
Not Used
Not Used
Not Used
A/D converter power source voltage: GND (0 Volts) The power source voltage to drive
the A/D converter. Connected to GND.
Reference Voltage input terminal. A reference voltage applied to the A/D converter in the
LSI. Connected to GND. (0 Volts)
Oven lamp, fan motor and turntable motor driving
10.7 msec.
H: GND
signal. To turn on and off shut off relay. The
square waveform voltage is delivered to the
L: -5V
During Cooking
RY1 driving circuit and RY2 control circuit.
Magnetron high-voltage circuit driving signal.
OFF
H: GND
Maximun
To turn on and off the cook relay (RY2). The signals
Output
ON
L: -5V
holds” L-level during microwave cooking and “H” level
OFF
OFF
H: GND
24
sec.
while not cooking. In other cooking modes (variable
70% Output
ON
cooking) the signal turns to “H” level and ‘L” level in
L: -5V
8 sec
repetition according to the power level.
Not Used
To input signal which communicates the door open/close information to LSI.
Door close “H” level signal (0V). Door Open “L” level -5V.
Not Used
AH sensor input. This input is an analog input terminal from the AH sensor circuit, and
connected to the A/D converter built into the LSI.
Used for initial balancing of bridge circuit (absolute humidity sensor). This input is an analog
input terminal from AH sensor circuit, and connected to the A/D converter built into the LSI.
A/D converter power source voltage : -5.0V. The power source voltage to drive the A/D
converter.
H: GND
Signal synchronized with commercial power
source frequency. This is the basic timing for
L: -5V
time processing of LSI.
16.7 msec
Used for initial balancing of the bridge circuit absolute humidity sensor.
Used for initial balancing of the bridge circuit absolute humidity sensor.
Used for initial balancing of the bridge circuit absolute humidity sensor.
Terminal to input the program to LSI.
Used for initial balancing of the bridge circuit absolute humidity sensor.
Used for initial balancing of the bridge circuit absolute humidity sensor.
3-12
Troubleshooting and Testing
Pin# Signal
P51
30
P52
31
I/O
OUT
OUT
Description
Signal to Buzzer: Duration
Signal to sound buzzer: PWM
Buzzer
ON
“Lingering”: PWM still “ON”
while Duration is “OFF”
PWM
OFF
OFF
Duration
ON
32
P53
OUT
33
P54
OUT
34
P55
OUT
35
P56
OUT
36
P57
OUT
37
P80
OUT
38
P81
OUT
39
P82
OUT
40
P83
OUT
41
P84
OUT
42
P85
OUT
43
P86
OUT
44
P87
OUT
45
46
47
48
49
50
51
52
53
54
55
56
57
P22
AIN7
P50
VEP
COM3
COM2
COM1
COM0
V3
V2
V1
C1
C0
OUT
IN
OUT
OUT
OUT
OUT
OUT
IN
IN
IN
Signal coming from touch key. When G1 line on key matrix is touched, a corresponding
signal out of P80-P87 is input into P53. When no key is touched, signal is held at “H” level.
Signal coming from touch key. When G2 line on key matrix is touched, a corresponding
signal out of P80-P87 is input into P54. When no key is touched, signal is held at “H” level.
Signal coming from touch key. When G3 line on key matrix is touched, a corresponding
signal out of P80-P87 is input into P55. When no key is touched, signal is held at “H” level.
Signal coming from touch key. When G4 line on key matrix is touched, a corresponding
signal out of P80-P87 is input into P56. When no key is touched, signal is held at “H” level.
Signal coming from touch key. When G5 line on key matrix is touched, a corresponding
signal out of P80-P87 is input into P57. When no key is touched, signal is held at “H” level.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P80 terminal while one of G6 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P81 terminal while one of G7 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P82 terminal while one of G8 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P83 terminal while one of G9 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P84 terminal while one of G10 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P85 terminal while one of G11 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P86 terminal while one of G12 line keys on key matrix is touched.
Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P53-P57
and P87 terminal while one of G13 line keys on key matrix is touched.
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
3-13
Troubleshooting and Testing
Notes
3-14
Component Teardown
TO PREVENT AN ELECTRIC SHOCK, TAKE THE FOLLOWING PRECAUTIONS:
1. BEFORE WIRING:
1) Disconnect the power supply.
2) Open the door and wedge the door open.
3) Discharge the high voltage capacitor and wait for 60 seconds.
2. DO NOT LET WIRE LEADS TOUCH TO THE FOLLOWING PARTS:
1) High voltage parts:
Magnetron, High voltage transformer, High voltage capacitor and High voltage rectifier assembly.
2) Hot parts:
Oven lamp, Magnetron, High voltage transformer and Oven cavity.
3) Sharp edge:
Bottom plate, Oven cavity, Waveguide flange, Chassis support and other metallic plates.
4) 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.
AVOID POSSIBLE EXPOSURE TO MICROWAVE ENERGY. PLEASE FOLLOW INSTRUCTIONS BELOW
BEFORE OPERATING THE 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.
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
Component Teardown
Outer Case Removal
Power Transformer Removal
Removal
1. Disconnect oven from power supply before
removing outer case.
2. Discharge the high voltage capacitor before
touching any oven components or wiring.
To remove the outer case, proceed as follows;
1. Disconnect the power supply cord.
2. Open the oven door and block it open.
3. Remove the two (2) screws from the lower portion of
rear cabinet using a T20H Torx type or GTXH20-100
screwdriver.
4. Remove the remaining two (2) screws from rear and
four (4) screws along the right side of outer case.
5. Slide the entire outer case back out about 1 inch
(3 cm) to free it from retaining clips on the cavity face
plate.
6. Lift entire outer case from the unit.
1. Disconnect the oven power supply cord and remove
outer case.
2. Open the oven door and block it open.
3. 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.
4. Disconnect wire leads (primary and high voltage)
from power transformer and the filament leads from
the magnetron and capacitor terminals.
5. Remove four (4) screws holding transformer to
bottom plate.
6. Remove transformer from bottom plate.
Re-Install
When replacing outer case, the two (2) special Torx
screws must be reinstalled in the same locations.
1. Rest transformer on the bottom plate with its primary
terminals toward the oven face plate.
2. Secure transformer with four screws to bottom plate.
3. Re-connect wire leads (primary and high voltage) to
power transformer and filament leads of transformer
to magnetron and high voltage capacitor. Refer to
Wiring Diagram.
4. Re-install outer case and check that oven is
operating properly.
Special Screw
Screw Driver
(Type: TORX T20 H or GTXH20-100)
Figure 4-1. Outer Case Removal
4-2
Component Teardown
High Voltage Rectifier and High
Voltage Capacitor Removal
Magnetron 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.
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. 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.
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 high voltage wire A from the high
voltage capacitor. See Wiring Diagram.
5. Disconnect the high voltage wire of high voltage
rectifier assembly from the magnetron.
6. Disconnect the filament lead (short one) of the power
transformer from the high voltage capacitor.
7. Remove one (1) screw holding capacitor holder with
the high voltage rectifier to the base plate.
8. Disconnect rectifier terminal from capacitor.
High voltage rectifier assembly is now free.
9. Remove capacitor holder. Capacitor is now free.
Removal
4. Disconnect wire leads from magnetron.
5. Remove the two (2) screws holding the chassis
support to the magnetron and the oven cavity front
flange.
6. Slide the magnetron duct slightly so that the two (2)
screws at left hand side of the magnetron appear.
7. Carefully remove the four (4) screws holding
magnetron to waveguide flange.
8. Remove the magnetron with care so that the
magnetron antenna is not hit by any metal object
around the antenna.
9. Now, the magnetron is free.
Re-Install
When replacing high voltage rectifier and high
voltage capacitor, ground side terminal of the high
voltage rectifier must be secured firmly with a
grounding screw.
1. Re-install the magnetron to waveguide flange with
care to prevent damage to the magnetron antenna.
2. Secure the magnetron with the four (4) screws.
3. Hold the chassis support to the oven cavity front plate
and the magnetron with the two (2) screws.
4. Reconnect the wire leads to the magnetron. Refer to
Wiring Diagram.
5. Re-install outer case and check that the oven is
operating properly.
When replacing the magnetron, be sure the R.F.
Gasket is in place and mounting screws are
tightened securely.
4-3
Component Teardown
Oven Lamp and Lamp Socket
Removal
Positive Lock® Connector (No-Case
Type) Removal
1. Disconnect oven from power supply and remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
1. Disconnect oven from power supply and remove
outer case.
2. Open the door and block it open.
3. 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.
4.
5.
6.
7.
8.
Pull the wire leads from the oven lamp socket.
Remove support bracket and the magnetron duct.
Unscrew the oven lamp from the lamp socket.
Remove socket from magnetron duct.
Now, the oven lamp and socket are free.
Terminals
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.
When connecting the positive lock® connectors to
the terminals, connect the positive lock® so that
the lever faces you.
Socket
Terminal
Magnetron Duct
Positive lock
connector
1
Oven Lamp
Push
Lever
2
Figure 4-2. Oven Lamp Socket
Pull down
Positive Lock®, Connector
Figure 4-3. Positive Lock® Connector
4-4
Component Teardown
Fan Motor Removal
Removal
1. Disconnect the oven power supply cord and remove
outer case.
2. Open the door and block it open.
3. 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.
4. Disconnect the wire leads from the fan motor.
5. Remove the two (2) screws holding the fan motor to
the oven cavity back plate.
6. Remove the fan blade from the fan motor shaft
according to the following procedure.
7. Hold the edge of the rotor of the fan motor by using a
pair of groove joint pliers.
Installation
Install the fan blade to the fan motor shaft according to
the following procedure:
1. Hold the center of the bracket which supports the
shaft of the fan motor on the flat table.
2. Apply the screw lock tight into the hole (for shaft)
of the fan blade.
3. 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.
3. Reset the fan duct assembly to its install position.
* Do not hit fan blade with excessive force when
installing because the bracket may be disfigured.
* Make sure that the fan blade rotates smooth
after installation.
* Make sure the axis of the shaft is not slanted.
5. Install the fan motor to the oven cavity back plate
with the two (2) screws.
6. Connect the wire leads to the fan motor, referring to
the wiring diagram.
Coil
Make sure that any pieces do not enter the gap
between the rotor and the stator of the fan motor
because the rotor is easily 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 bracket by touching with pliers.
Do not reuse the removed fan blade because the
hole (for shaft) may be larger than normal.
Groove
joint pliers
Bracket
Stator
Gap Rotor
Rear View
Shaft
Axis
These are the positions that
should be pinched with pliers.
Stator
Shaft
Rotor
Side View
8. Remove the fan blade from the shaft of the fan motor
by pulling and rotating the fan blade with your hand.
9. Now, the fan blade and the fan motor will be free.
Table
Center of
bracket
Figure 4-4. Fan Motor Components
4-5
Component Teardown
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.
Servicing The Touch Control Panel
Precautions For Handling Electronic Components
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.
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 sensor
related controls of the touch control panel by using the
dummy resistor(s).
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:
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.
4. Disconnect leads to the primary of power transformer.
5. Ensure leads remain isolated from other components
and oven chassis by using insulation tape.
6. 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 leads to the primary of 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 (sensor
related ones included) of the touch control panel
Servicing Tools
Tools required to service touch control panel assembly.
1. Soldering iron: 30W (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.
4-6
Component Teardown
Installation
1. Remove remaining adhesive on the control panel
frame surfaces with a soft cloth soaked in alcohol.
2. Make sure that the VFD (Vacuum Fluorescent
Display) is in good condition.
3. Remove the backing paper from the new graphic
sheet.
4. Adjust the upper edge and left edge of the graphic
sheet to the large depression on the surface of the
control panel frame.
5. Attach the graphic sheet to the control panel frame
by rubbing with a soft cloth not to scratch.
6. Reinstall the control panel frame to the oven.
Control Panel Assembly Removal
1. Disconnect the oven power supply cord and remove
outer case.
2. Open the door and block it open.
3. 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.
4. Disconnect the wire leads from panel components.
5. Remove the one (1) screw holding the control panel
assembly to the oven cavity front plate.
6. Slide control panel assembly upward and remove.
7. Now, individual components can be removed.
Do not touch contact surface of ribbon cable (edge).
Control Panel Frame
1. Before attaching a new key unit, wipe off remaining adhesive on the control panel frame surfaces
completely with a soft cloth soaked in alcohol.
2. When attaching key unit to control panel frame,
adjust upper edge and right edge of the key unit
to the correct position of control panel frame.
3. Place the key unit firmly to the control panel
frame by rubbing with soft cloth not to scratch.
Ribbon
Cable
Key Sheet Replacement
1. Disconnect the oven power supply cord and remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
Key
Unit
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.
Control Unit
Control Panel Frame
(Rear side)
4. Remove the control panel assembly, referring to
Control Panel Assembly Removal.
5. Remove the five (5) screws holding the control unit to
the control panel frame. And remove the control unit
by releasing from tabs.
6. Remove the key sheet from the control panel frame.
(Heat gun will soften adhesive)
4-7
Figure 4-5. Control Panel Assembly
Component Teardown
Door Sensing Switch/Primary Switch/
Third Door Switch And Monitor
Switch Removal
Door Sensing Switch/Primary Switch/
Third Door Switch And Monitor Switch
Adjustment
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.
1. Disconnect the oven power supply cord and remove
outer case.
2. Open the door and block it open.
3. 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.
4. Disconnect the wire leads from the switch.
5. Remove two (2) screws holding latch hook to oven
flange.
6. Remove latch hook assembly from oven flange.
7. Push outward on the two (2) retaining tabs holding
switch in place.
8. Switch is now free. At this time switch lever will be
free, do not lose it.
Reinstall
1. Re-install each switch in its place. The third door
interlock/ monitor switches are in the lower position
and the door sensing switch is in the upper position.
2. Re-connect wire leads to each switch. Refer to
wiring diagram.
3. Secure latch hook (with two (2) mounting screws) to
oven flange.
4. Make sure that the monitor switch is operating
properly and check continuity of the monitor circuit.
Refer to “Test Procedure and Adjustment Procedure”
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.
If the door sensing switch, primary switch, secondary
switch and monitor switch do not operate properly due
to a misadjustment, the following adjustment should be
made.
4. Loosen the two (2) screws holding latch hook to the
oven cavity front flange.
5. 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 the latch hook should be adjusted
so that the door sensing switch, primary switch and
third door switch are activated with the door closed.
The horizontal position of the latch hook should be
adjusted so that the plunger of the monitor switch is
pressed with the door closed.
6. Secure the screws with washers firmly.
7. Check the operation of all switches. If each switch
has not activated with the door closed, loosen screw
and adjust the latch hook position.
(continued next page)
4-8
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 the 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, primary switch and third
door switch interrupt the circuit before the door can
be opened.
3. Monitor switch contacts close when door is opened.
4. Re-install outer case and check for microwave
leakage around door with an approved microwave
survey meter.
1. Disconnect the power supply cord.
2. Push the open button and open the door slightly.
3. Insert a putty knife (thickness of about 0.5mm) into
the gap between the choke cover and door frame as
shown in Figure 4-7 to free engaging parts.
4. Pry the choke cover by inserting a putty knife as
shown Figure 4-7.
5. Release choke cover from door panel.
6. Now choke cover is free.
7. Release two (2) pins of door panel from two (2) holes
of upper and lower oven hinges by lifting up.
8. Now, door panel with door frame is free from oven
cavity.
Latch Heads
When carrying out any repair to the door, do not
bend or warp the slit choke (tabs on the door
panel assembly) to prevent microwave leakage.
Door Sensing
Switch
Door
Monitor Switch
Third Door
Switch
Switch Lever
Primary
Switch
Figure 4-6. Door Switch Components
9. Release the door panel from twelve (12) tabs of door
frame.
10. Remove the door panel from the door frame.
11. Now, door panel with sealer film is free.
12. Tear sealer film from door panel.
13. Now, door panel is free.
14. Slide latch head upward and remove it from door
frame with releasing latch spring from door frame and
latch head.
15. Now, latch head and latch spring are free.
16. Remove door screen from door frame
17. Now, door frame is free.
Choke Cover
Door Frame
Putty Knife
Figure 4-7. Door Components
4-9
Component Teardown
Re-Install
1. Re-install door screen to door frame.
2. Re-install the latch spring to the latch head. Re-install
the latch spring to the door frame. Re-install latch
head to door frame.
3. Re-install door panel to door frame by fitting twelve
(12) tabs of door frame to twelve (12) holes of door
panel.
4. Put sealer film on door panel. Refer to “Sealer Film”
about how to handle new sealer film.
5. Catch two (2) pins of door panel on two (2) holes of
upper door frame.
6. Re-install choke cover to door panel by pushing.
After any service to the door:
(A) Make sure that door sensing switch, primary switch
and secondary switch are operating properly. (Refer
to Section 3 “Test Procedures”.).
(B) An approved microwave survey meter should be
used to assure compliance with proper microwave
radiation emission limitation standards.
Sealer Film
After any service, 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. Check for microwave leakage around door with an
approved microwave survey meter. (Refer to
Microwave Measurement Procedure.)
Pin
Upper
Oven Hinge
The door on a microwave oven is designed to act
as an electronic seal preventing the leakage of
microwave energy from the oven cavity during the
cook cycle. This function does not require that the
door be airtight, moisture (condensation)-tight
or light-tight. Therefore, occasional appearance
of moisture, light or sensing of gentle warm air
movement around the oven door is not abnormal
and do not of themselves indicate a leakage of
microwave energy from the oven cavity. If such
were the case, the oven could not be equipped
with a vent, the very purpose of which is to exhaust
the vapor-laden air from the oven cavity.
1. Put the adhesive tape on the backing film of the
sealer film as shown in Fig. 4-9.
2. Tear the backing film by pulling the adhesive tape.
3. Put the pasted side of the sealer film on the door
panel.
Sealer Film
Backing Film
Adhesive
Tape
Figure 4-9. Sealer Film
Turntable Motor Removal
Upper Oven
Hinge
Lower
Oven Hinge
Lower Oven
Hinge
Pin
Choke Cover
Figure 4-8. Door Replacement and Adjustment
1. Disconnect the power supply cord.
2. Remove the turntable tray, and the turntable support
out of the oven cavity.
3. Lay oven on its backside. Remove turntable motor
cover by snipping off the material in four corners.
4. Where the corners have been snipped off bend
corner areas flat. No sharp edges must be evident
after removal of the turntable motor cover.
5. Disconnect wire leads from turntable motor.
(See “Positive Lock Connector Removal”)
6. Remove one (1) screw holding turntable motor to
oven cavity.
7. Now the turntable motor is free.
8. After replacement use the one (1) screw to fit the
turntable motor cover.
4-10
Wiring Diagrams
Wiring Schematic
Oven Off Condition
120 VAC
60Hz
WHT
H
BLK
L
NOTE: Condition Of Oven
1. Door Closed
2. Clock Appears On Display
GRN
N
GND
SCHEMATIC
RED
WHT
GRY
C1
C3
NOISE
FILTER
C2
GND
CAVITY TEMP
FUSE
RED
N.O.
WHT
RY2
SECONDARY
INTERLOCK
RELAY
C/T FUSE
BLK
N.O.
COM.
GRY
RY1
OVEN
LAMP
RELAY
BLU
ORG
ORG
TURNTABLE
MOTOR
FM
DOOR
SENSING
SWITCH
N.C.
COM
BRN
RED
HIGH
VOLTAGE
CAPACITOR
MAGNETRON
5-1
POWER TRANSFORMER
N.O.
YLW
COM.
MONITOR
SWITCH
GRY
HIGH
VOLTAGE
RECTIFIER
BLK
BRN
FAN
MOTOR
WHT
WHT
WHT
PRIMARY
INTERLOCK
SWITCH
N.O.
TTM
B2
B1
WHT
COM
OVEN
LAMP
F3
F2
F1
HUMIDITY
SENSOR
OL
COM.
GRY
CONTROL UNIT
THIRD
DOOR
SWITCH
1
CNC
RED
5-2
COM.
GRY
RY2
2
GRY
CN-F
WHT
N.O.
N.O.
WHT
RY1
COM.
T1
BLU
BLK
ORG
GRY
GRY
NOTE:
Hot (ORG
connect ed
with blue
light socke
BLUE MA R
ORG
OVEN LAMP
AND SOCKET
BLK
N.C.
PRIMARY
SWITCH
COM.
NO
BLU
RED
RED
YLW
ORG
RE D
BLK
COM.
NO
THIRD DOOR
SWITCH
WHT
RED
COM.
WHT
C/T FUSE
RED
CAVITY TEMP. FUSE
BLK
H
MONITOR
SWITCH
WHT
BLK
(POWER UNIT)
CN-B
SECONDARY
INTERLOCK
RELAY
R ED
WHT
W HT
N
GRY
BRN
YLW
WHT
GRN
WHT
TURNTABLE
MOTOR
GRN
ORG
COM.
DOOR
SENSING
SWITCH
MAGNETRON
POWER
TRANSFORMER
H.V. RECTIFIER
HIGH VOLTAGE
WIRE A
N.O.
HIGH
VOLTAGE
CAPACITOR
HIGH VOLTAGE COMPONENTS
FAN MOTOR
WHT
CN-B
1 P NK
2 GRN
NOTE:
The grounding conductor of
the power supply cord has
been grounded by power
supply cord fixing screw.
The screw must always be
kept tight.
to Oven cavity
POWER SUPPLY
CORD 120V 60Hz
N
NOTE:
The neutral (WHT/GRY) wire must
be connected to the terminal with
"N" mark on the power supply
cord.
H
PNK
GRN
Wiring Diagrams
Pictorial Diagram
5-3
CF
CF
IC-2
1 2 3 4
8 7 6 5
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Wiring Diagram
Wiring Diagrams
Wiring Diagrams
Notes
5-4
Parts List
NOTE: The parts marked “ ” may cause undue microwave exposure.
The parts marked “*” are used in voltage more than 250V.
DESCRIPTION
REF. NO.
Q’TY
ELECTRICAL PARTS
* 1
2
3
4
5
6
7
8
9
10
11
12
13
High voltage assembly
Lamp socket
Oven lamp
Fan motor
Monitor switch (V-16G-2C25), C/T fuse (20A 250V AC) & Inst.
Primary interlock switch and door sensing switch (V-5230Q)
Cavity temperature fuse 150ºC
Magnetron
Turntable motor
Power transformer
Power supply cord
AH Sensor
Noise filter
1
1
1
1
1
3
1
1
1
1
1
1
1
CABINET PARTS
14
15
16
Base plate
Foot
Outer case cabinet
1
4
1
CONTROL PANEL PARTS
17
18
19
20
21
22
23
CPU assy
Control panel sub assembly
Key unit
Open button
Open button spring
Screw; 3mm x 6mm
User caution label
1
1
1
1
1
5
1
OVEN PARTS
24
25
26
27
28
29
30
31
32
33
34
35
1
1
1
1
1
1
1
1
1
1
1
1
H.V. Capacitor band
Chassis support
Latch hook
Switch lever
Magnetron duct
Fan blade
Fan duct
Bottom filler
Waveguide cover
Turntable motor packing
Sensor duct
Mag cushion
DOOR PARTS
36
37
38
39
40
41
42
43
44
Door assembly
Door frame assembly
Latch head
Latch spring
Door panel
Sealer film
Choke cover
Door stopper
Screw NOTE: Supplied on higher level assembly
6-1
1
1
1
1
1
1
1
1
1
Parts List
DESCRIPTION
REF. NO.
Q’TY
ELECTRICAL PARTS
45
46
47
48
49
50
51
52
Main wire harness
Turntable support
Turntable tray
Monitor caution label
DHHS/Screw caution label
Operation manual
High voltage wire A
NHW caution label
1
1
1
1
1
1
1
1
SCREWS, NUTS AND WASHERS
53
54
55
56
57
58
59
60
61
62
63
Special screw
Special screw
Screw : 4mm x 12mm
Screw : 4mm x 12mm
Screw : 3mm x 8mm
Screw : 4mm x 8mm
Special screw (Torx tamper proof screw)
Screw
Screw : Outercase screws
UL screw label
Built-in height label
6-2
5
3
1
17
5
4
2
1
1
1
1
Parts List
Oven And Cabinet Parts
59
59
56
16
61
30
56
49
62
57
54
12
63
7
52
4
56
61
57
29
55
34
13
11
56
57
58
5
58
25
32
60
8
35
48
54
54
47
26
33
9
57
10
2
28
5
14
46
53
6
6
6
53
27
24
3
1
31
56
15
15
56
15
15
6-3
x4
56
Parts List
Control And Door Parts
18
22
23
17
19
21
43
20
41
42
36
40
37
38
E
L
E
C
T
R
O
L
U
X
39
45
51
Actual wire harness may be different from illustration.
6-4
Parts List
Packing and Accessories
TOP PAD ASSEMBLY
DOOR PROTECTION SHEET
47 TURNTABLE TRAY
PLASTIC BAG
On Top Of Oven
TRAY HOLDER
50
OPERATION MANUAL
EN
OV
E
TH TY
O AVI
T
C
IN
46 TURNTABLE SUPPORT
PACKING CASE
Non-replaceable items.
6-5
BOTTOM PAD ASSEMBLY
Parts List
Notes
6-6