Troubleshooting Guide - LG 505E Series Service Manual

NO POWER
(POWER INDICATOR OFF)
FUSE OK?(F901)
D900 BRIDGE DIODE?
C908(+) VOLTAGE
145VDC at 110V input
1 2
310VDC at 220V input
IC901, Q901
D971, D961, D951, D904
D941, D942, D906 ?
TROUBLE IN
Q951, Q952, Q941, Q942,
Waveforms
1
Q901, Drain

TROUBLESHOOTING GUIDE

1. NO POWER
CHECK
YES
CHECK
YES
CHECK
YES
CHECK
YES
2
TROUBLE
NO
IN FUSE (F901)
SMPS Switch (ON, OFF)
NO
NO
TROUBLE IN
IC901, Q901
NO
IC901, #6
- 16 -
TROUBLE IN
BRIDGE DIODE (D900)
TROUBLE IN
D971, D961, D951, D904
D941, D942, D906