Electrical Troubleshooting Guide; Power (Smps) - LG CM5660 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER (SMPS)

No 12 VA
F901 normal?
BD901 normal?
TH901(TH903) normal?
Is Vcc
(10 V ~ 18 V) supplied to
IC901 pin7?
D933 normal?
Is there
about 2.5 V at
IC941 pin1?
D951 normal?
ZD932 normal?
Power line of main PCB is short.
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
Replace F901 (Use the same fuse).
NO
NO
NO
Check or replace D902.
NO
NO
NO
NO
3-22
Replace BD901.
Replace TH901.
D902 normal?
NO
Replace D933.
Replace IC941.
Replace D951.
Replace ZD932.