Electrical Troubleshooting Guide; Power Supply On Smps Board - LG LAP340 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER SUPPLY ON SMPS BOARD

No 20 VA
Q901 normal?
D951/ D952 normal?
IC901 normal?
Is the VCC
(11 V ~ 25 V) supplied to
IC901 Pin5?
Power line of main PCB is short.
NO
YES
NO
YES
NO
YES
NO
YES
Replace D951/ D952.
Check or replace Q902.
3-7
Replace Q901.
Replace IC901.
Q902 normal?
NO