BenQ Q7T4-FP71G, Service Manual

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Q7T4-FP71G LCD Monitor Service Guide
Trouble Shooting
3
Confidential
Backlight didn't shine
LED shined?
3.3V existed? IS I/F board connected?
IC801 PIN 9 IS 15V? Replace Q761
PWM existed?
(BLT_ADJ)
Plug CN701 again or
checking I/F BD
Turn on level existed?
(BLT_ON)
Insert them again
Check CN801, CN802
was pluged properly?
Plug CN601 again or
checking PW BD
Replace IC801,Q805
Replace new fuse
Replace new fuse
Check IC701 OK?
Checking F601
Broke?
Check IC601 Vcc
existed?
Replace IC602,
IC702,D701 or check
I/F BD
Replace IC701
Replace new fuse
Replace
IC601,Q602,Q603
R602
Y
N
N
N
N
Y
Y
Y
Y
N
Y
Y
N
N
Y
Y
Y
N
N
N