Philips 170V7 Service Manual page 44

17" LCD Color Monitor
Inverter board
No power
Check C811 (+) =12V
Check ON/OFF signal
Check U811 pin 2=12V?
Check U811 Pin1/pin15 have the output of sawtooth wave at short time
Check Q821/Q841 pin5/pin8 is 12V?
Check PT801/PT802 pin7/pin8= 650V?
Replace backlight
NG
OK
NG
OK
NG
OK
NG
Check U811 pin 5/pin6
OK
NG
Cut all the pin connector of Q821/Q841, check C811 (+)=12V?
OK
NG
OK
Check adapter section
Check Interface section or main board
Check Q801
NG
OK
NG
OK
Replace Q821/Q841
Unplug backlight connector wire, check
PT801/PT802 pin7/pin8 = 650V?
OK
NG
Replace PT801/PT802
44
Replace U811
Check Q801
170V7