Electrical Troubleshooting Guide; System Power Supply On Smps Board - LG BH5140S Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. SYSTEM POWER SUPPLY ON SMPS BOARD

No 3.8 VA.
Is F901 normal?
Is TH901 normal?
Is BD901 normal?
Is the VCC (11 V ~ 25 V) supplied to IC902 pin5?
Power Line of MAIN PCB is short.
No 6 VA.
Is F901 normal?
Is TH901 normal?
Is BD901 normal?
Is the VCC (11 V ~ 25 V) supplied to IC902 pin5?
Power Line of MAIN PCB is short.
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
Replace F901. (same fuse)
NO
NO
NO
NO
Replace F901. (same fuse)
NO
NO
NO
2-41
Replace TH901.
Replace BD901.
Is D918 normal?
YES
Check or replace D918.
Replace TH901.
Replace BD901.
Is D952 normal?
YES
Check or replace D952.