LG LMX21981** /01 Service Manual page 38

3. Open Door Detection Circuit Check
Measurement
Location
Freezer/
Refrigerator Door
Closed
Open
8-2-3 Temperature Sensor Circuit
The upper circuit reads refrigerator temperature, freezer temperature, Icing sensor temperature and defrost sensor
temperature for defrosting and the indoor temperature for compensating for the surrounding temperature into MICOM.
Opening or short state of each temperature sensor are as follows:
SENSOR
Freezer sensor
Refrigerator sensor
Defrosting sensor
Room Temperature sensor
Icing sensor
CHECK POINT
POINT Voltage
A
POINT Voltage
B
POINT Voltage
C
POINT D Voltage
POINT Voltage
E
Pin 11 & 12 of con4 Ref.Door
Pin 5 & 6 of con6 Fre.Door
5 V
0V
NORMAL (-30°C ~ 50°C)
0.5 V ~ 4.5 V
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SHORT-CIRCUITED OPEN
0 V 5 V