Asus MW221C - 8.2.5 Troubleshooting: W;LED, No Backlight

22" LCD Color Monitor ASUS MW221C
39
2.) W / LED, No Backlight
Check CN902 pin4, 5 = 12V
NG
OK
Check adapter or MB
Check ON/OFF signal
Check Interface board
NG
OK
Check IC801 PIN12=12V
NG
OK
Change Q801
Check IC801 PIN10, 9 have the output of square wave at short
NG
OK
Change IC801
Check Q804, Q809 PIN5, 6, 7, 8 have the output of square wave at short time.
NG
OK
Check Q804, Q805, Q806, Q809, Q810, Q811
Check the output of PT801, PT802
Check connecter & lamp
OK
NG
Change PT801, PT802