Fast Track Troubleshooting
IMPORTANT SAFETY NOTICE – “For Technicians Only” This service data sheet is
intended for use by persons having electrical, electronic, and mechanical experience
and knowledge at a level generally considered acceptable in the appliance repair trade.
Any attempt to repair a major appliance may result in personal injury and property
damage. The manufacturer or seller cannot be responsible, nor assume any liability for
injury or damage of any kind arising from the use of this data sheet.
Model:
SMH7187STG/XAA
Note: There are 2 Versions
of this M/W, verify
Version to order parts.
Publication # tsSMH7187 Revision Date 03/21/2011
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Samsung 'Microwave' Diagnostic Code Quick Guide
Failure Code
E-11 Open
E-12 Short
E-13 T1 Max Time Error
E-14 Dry Up / No Load
E-21 Open
E-22 Short
E-23 T1 Max Time Error (Preheating not completed)
E-24 Over temperature error
E-25 Abnormal temperature is sensed at Micro Cook
E-26 Temp is not over the fixed AD in first 3 minutes after heater starts.
E-31 Open (When value of HEX is above ―FF‖ for 5 seconds)
E-32 Short
E-33 The initial value of HEX is under ―14‖ for 30 seconds while a weight
sensor in operation.
E-34 The initial value of K calculated by a weight
sensor is above and under ―±28‖ as value of HEX.
E-35 The value of A is ―-‖ as a weight sensor calculates.
E-41 Open
E-42 Short
E-43 T1 Max Time Error
E-44 Dry Up
E-45 Cooling Error (3minutes)
E-46 Primary Open Error(3minutes)
E-51 Open (Sense Failure)
E-53 Read/Write Error
E-54 Zero not to be set
E-61 Open
E-62 Short
E-63 T1 Max Time Error
-SE- Key Short Error (10 seconds)
E-01 Door opens when the door should not be opened.
E-02 Cooking Time Setting Over Error (MWO)
E-03 Cooking Time Setting Over Error (Grill)
E-04 Cooking Time Setting Over Error (Convection)
E-05 Cooking Time Setting Over Error (Combination)
E-06 It fails to sense that the swing heater has stopped for 20 seconds
during cooking.
E-08 In case function of MWO starts with spit inserted into cavity inside.
E-09 The damper is not set to be positioned for 2 minutes.
# tsSMH7187 RevA 03/21/2011
Cause
Error Code Gas Sensor Error Case (E-1X)
Error Code Temp Sensor Error Case (E-2X)
Error Code Gas Sensor Error Case (E-1X)
Error Code Easy/PH Sensor Error Case (E4)
Error Code EEPROM Error Case (E-5X)
Error Code Humidity Sensor Case (E-6X)
Error Code Others (E-0X, Letter)
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# tsSMH7187 RevA 03/21/2011
2
CN301 Gas Sensor
3-4 5vdc
CN601
1) KEY OUT-1
2) KEY OUT-2
3) KEY OUT-3
4) KEY OUT-4
5) KEY OUT-5
6) KEY OUT-6
7) KEY OUT-7
8) KEY OUT-8
9) KEY OUT-9
10) KEY IN-1
11) KEY IN-2
12) KEY IN-3
13) KEY IN-4
14) KEY IN-5
15) KEY IN-6
16) KEY IN-7
Main PCB
RY209
Vent
High
RY208
TT
CN401 Door Connector
1 Door sw
3 Door sw
3-5 12vdc
4-5 5vdc
RY207
Louver
RY206
Bright
Relay
RY05
Night
Relay
RY204
Power Low
Relay
RY203
Power
High Relay
RY211
Vent
Boost
CN202 Pwr & Relay
1-(CN201-1) Main
3-(CN201-1) TT
5-(CN201-1) Vent Low
7-(CN201-1) Vent High
9-(CN201-1) Vent Boost
RY210
Vent
Low
RY201
Main
Relay
RY202 In
Rush Relay
CN201 Relay, Lamp, SMPS
1 Line 1
3-1 RY202 In Rush Relay Neutral Contact
5-1 RY206 Bright Lamp Relay Neutral Contact
5-1 RY205 Night Lamp Relay Neutral Contact
7-1 RY207 Louver
The fuse is located on the noise filter.
Door Interlock Ass’y
1. Disconnect power and remove grille and Assembly
Control Box.
2. Replace the fuse.
3. When 20A fuse blows out by the operation of interlock
monitor switch failure, replace the primary interlock
switch, secondary interlock switch, door sensing switch,
interlock monitor switch and power relay.
4. When the above four switches operate properly, check
if any other part such as the control circuit board, blower
motor or high voltage transformer is defective.
# tsSMH7187 RevA 03/21/2011
3
Microwave Cooking Wattage Test
Fill a 1000ml plastic room temperature container with cool tap water,
temperature of the water should be 55-65 degrees
Stir water with a thermometer and record the water temperature, remove
thermometer.
Place the container in the center of the lowest shelf or center of the
bottom of the microwave.
For units less than 1550 watts, operate the oven on high for exactly 63
seconds.
Using the thermometer, stir the water to check the temperature of the
water.
Subtract the starting temperature from the final temperature; this will be
the temperature rise.
Temp Rise
Output
Temp Rise
Out-
5
194
23
891
6
232
24
930
7
271
25
969
8
310
26
1007
9
349
27
1046
10
387
28
1085
11
426
29
1124
12
464
30
1162
NOTE: Check line voltage under load, lower line voltage will lower
the power output.
13
504
31
1201
14
542
32
1240
Procedure for measurement of microwave energy leakage
15
581
33
1279
16
620
34
1317
17
659
35
1356
18
697
36
1395
3. Set survey meter with dual ranges to 2,450MHz.
19
736
37
1434
4. When measuring the leakage, always use the 2 inch spacer cone
with the probe. Hold the probe perpendicular to the cabinet door.
Place the spacer cone of the probe on the door and/or cabinet door
seam and move along the seam. The door viewing window and the
exhaust openings moving the probe in a clockwise direction at a
rate of 1 inch/sec. If the leakage testing of the cabinet door seam is
taken near a corner of the door, keep the probe perpendicular to
the areas making sure that the probe end at the base of the cone
does not get closer than 5 cm to any metal. If if gets closer than 5
cm, erroneous readings may result.
20
775
38
1472
21
814
39
1511
22
852
40
1550
1.
Pour 275±15cc of 20±5°C(68±9°F) water in a beaker which is
graduated to 600cc, and place the beaker in the center of the oven
2. Start to operate the oven and measure the leakage by using a microwave energy survey meter.
5. Measured leakage must be less than 4mW/cm2 after repair and
adjustment.
Maximum allowable leakage is 5mW/cm2. 4mW/cm2 is used to allow
for measurement and meter accuracy.
M/W Information
M/W Power
1100 Watts
M/W Weight
54.23 Lbs
Primary
0.43Ω
Secondary
125-130Ω
Filament
0.0Ω
Vent Turbo
21Ω
Vent High
45Ω
TT & Stirrer Motors
120Ω
Fan Motor
32-40Ω
Specifications
High Voltage
Transformer
Motors
# tsSMH7187 RevA 03/21/2011
Safety precautions
Some semiconductor (―solid state‖) devices
are easily damaged by static electricity. Such
components are called Electrostatically
Sensitive Devices (ESDs). Examples
include integrated circuits and field-effect
transistors. Immediately before handling any
semiconductor components or assemblies,
drain the electrostatic charge from your body
by touching a known earth ground.
High Voltage Warning Do not attempt to
measure any of the high voltages --this includes the filament voltage of the magnetron.
High voltage is present during any cook cycle.
Before touching any components or wiring,
always unplug the oven and discharge the
high voltage capacitor
WARNING: It is critical to route wires and
wire harness identical to the way they were,
to prevent electromagnetic interference causing possible fault codes.
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