Trouble Shooting; No Power - Dell 2707WFP Service Manual

27" LCD Color Monitor

9.2 Trouble shooting

9.2.1 Main Board

No power

No power
Press power key and look if
the picture is normal
The AC of 100-240 is normal Please
reinsert and make sure
OK
Measure Q711 PIN 5/6/7/8 = 1.8 V
U702 PIN 2 = 3.3 V
OK
X401 X301 and X501
Oscillate waveforms are normal?
OK
Replace U301, U401, U501
NG
U701 PIN 2 = 2.5 V
NG
NG
Replace X401,
X301, and X501
Reinsert or check the
power section
Measure CN701 PIN7/8/9 = 12 V
CN701 PIN14 = 5 V
NG
OK
Replace U706, Q711, U701, U702
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Dell 2707WFP
Check power section