Trouble Shooting - Lenovo L1900P Service Manual

19" LCD Color Monitor

8.2 Trouble Shooting

8.2.1 Main Board
(1). 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 U701 PIN2=3.3V
Measure Q703 V =1.8V
collector
OK
X401 oscillate waveforms
are normal
OK
Replace U401
Reinsert or check the
NG
Adapter/Inverter section
NG
Replace U701, Q702, Q703
NG
Replace X401
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Lenovo L1900P