LG Flatron W2234S - Troubleshooting Screen Display; Black Screen and MCU Failures

5. Black Screen and backlight turn on
Black Screen
Power Fail
Check power supply:
Pin1, 2 of CN101
Check pin4,6 , and 51
Of U105
Check Crystal: Pin1,
Pin2
Of U105
Check CCFL
-
Enable
(pin55) of U105
MCU Fail
Check D101
Check: X101,
C157,C158,R137,R138
Inverter Fail
OK
NG
OK
Check Reset (pin54)
Of U105
Check pin5 of
CN101
Check R103, Q103
R102,R105,R106
Check C164, R153
NG
NG
OK OK
Check pin30,and 53
Of U105
And U101
Check
U102
NG
NG
NG
OK
OK
OK
NG
19