Warm Drawer Does Not Heat - LG LSRG309ST Service Manual

CHECKING FLOW CHART BY FAILURE
Warm drawer does not
heat
Yes
Power Off
1
Is the disconnect or loose
connector?
1. Between Main PCB and
Relay PCB (CN7,CN8)
2. Electric wiring of relay PCB (CN10)
3. Electric wiring of drawer heater
CN8 CN8 CN8 CN8 CN8 CN8 CN8
CN8 CN8 CN8 CN8 CN8 CN8
CN8 CN8 CN8 CN8
CN8 CN8 CN8 CN8 CN8
CN7 CN7 CN7 CN7 CN7
CN7 CN7 CN7 CN7
CN7 CN7 CN7 CN7 CN7 CN7
CN7 CN7 CN7 CN7 CN7 CN7 CN7
No
Reconnect or
Yes
repair the
connector
CN10 CN10 CN10
CN10 CN10 CN10 CN10 CN10 CN10
CN10 CN10 CN10 CN10 CN10 CN10
CN10 CN10 CN10 CN10
CN10 CN10 CN10
10-7
Power Off
2
Is the drawer heater normal?
Measure the resistance
of drawer heater
Normal - approximately 24Ω
4pin 4pin 4pin 4pin 4pin
4pin 4pin 4pin 4pin 4pin 4pin
4pin 4pin 4pin 4pin
4pin 4pin 4pin
Yes
3
Replace the Relay PCB
(EBR52349701)
If it doesn't work even though changing the Relay PCB,
you should replace the Main PCB.
(EBR52349501)
No
Replace the
failed thermistor
3pin