LG LSWS305ST Service Manual page 38

CHECKING FLOW CHART BY FAILURE MODE
Dead
1
Is it 120V AC?
Check the power transformer(Refer to the below)
Primary
Secondary1
Secondary2
Power off
Check the Thermostat (open/short)
L1 and CN01's RD color wire
No
N and CN01's WH color wire
If it have the error, it is open state.
Is it short?
Yes
Is it OK?
Yes
2
5-6
No
Side Lead color
Primary 1 Black ~ white
Secondary 1 yellow ~ yellow approximately
Secondary 2 red ~ red
No
Replace the power transformer
Replace the thermostat.
END
Coil resistance
approximately
Under100[Ω]
Under 50 [Ω]
approximately
Under 50 [Ω]
END