AOC 712SI - Troubleshooting; Main Board Troubleshooting

17” LCD Color Monitor AOC 712Si
29
8.2 Trouble Shooting
8.2.1 Main Board
No Power (No LED indicator)
No picture（LED green）
Rewrite SW
NG
Check U3, U4=5v
NG
Check ada
p
ter and connector
OK
Check U2 supply voltage
NG
Check U2、U3 and U4 if OK
NG
Change defective component
OK
Check key circuit if ok
Chan
g
e defective com
p
onent
OK
Check U2 （
p
in PWR、RST ）and
NG
Chan
g
e defective com
p
onent
NG
The button under control
OK
Check U2 BL EN is hi
g
h volta
g
e
A
nal
y
se inverter
OK
NG
Change U2
Check U2、pin50 and pin51 waveforms
is normal
NG
Check C29 and Y1 is OK
Chan
g
e U2
NG
Chan
g
e defective com
p
onent
OK
NG