Backlight Didn't Shine - BenQ Q7T4-FP71G Service Manual

Q7T4-FP71G LCD Monitor Service Guide
Y
Replace Q761
N
Plug CN701 again or
checking I/F BD
N
Plug CN601 again or
checking PW BD
N
Check CN801, CN802
Insert them again

Backlight didn't shine

Y
IC801 PIN 9 IS 15V?
N
PWM existed?
(BLT_ADJ)
Y
Turn on level existed?
(BLT_ON)
Y
Check IC701 OK?
was pluged properly?
Y
Replace IC801,Q805
IC702,D701 or check
LED shined?
N
3.3V existed?
N
Y
N
Y
Checking F601
Broke?
N
Y
Check IC601 Vcc
existed?
N
Replace IC602,
I/F BD
Confidential
Trouble Shooting
Y
IS I/F board connected?
Y
Replace new fuse
Replace IC701
Replace new fuse
Replace
IC601,Q602,Q603
R602
N
Replace new fuse
3