Hanns.G AG172D, Service Manual

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17" LCD Color Monitor Hanns.G AG172D
39
2.) No Backlight
Check C811 (+) =12V
NG
OK
Check power section
Check ON/OFF signal
Check Interface section or main board
NG
OK
CheckIC801 pin 2=5V?
NG
OK
Check Q801 Q802 Q803 ZD801
Check IC801 Pin1/pin15 have the output of sawtooth wave at short time
NG
OK
Check IC801 pin 5/pin6
NG
OK
Replace IC801
Check Q805/Q806 pin5/pin8 is 12V?
Check PT801/PT802 pin7/pin8= 650V?
Cut all the pin connector of Q805/Q806, check C811 (+)=12V?
OK
NG
Unplug backlight connector wire, check
PT801/PT802 pin7/pin8 = 650V?
OK
NG
Replace backlight
Replace PT801/PT802
OK
NG
NG
Replace Q805/Q806
Check Q801 Q802
OK