Trouble Shooting - Optima L903AD+ Service Manual

19" LCD Color Monitor

8.2 Trouble Shooting

8.2.1 Main Board
No power
No power
Press power key and look
if the picture is normal
NG
Please reinsert and make sure
the AC of 100-240 is normal
OK
Measure D701(-)=1.8V
U702 PIN2=3.3V
OK
X401 oscillate waveforms
are normal
OK
Replace U401
NG
NG
NG
Replace X401
39
Optima L903AD+
Reinsert or check the
Adapter/Inverter
section
Check CN701, U701,
D701, D702, Q702