Acer AL1702 Service Manual page 37

5. No Backlight
Check C802 (+) =12V
OK
Check ON/OFF signal
OK
Check IC801 pin12=5V?
OK
Check the pin9&10 of IC801 have PWM wave
OK
Check the resonant wave
of pin6 & pin1 for PT801
OK
Check the output of PT801
Check connecter & lamp
NG
NG
NG
NG
NG
NG
OK
Change FB801,Check
Q808, Q810
Check Interface board
Change Q805.Q808 or Q810
Change IC801
OK
CheckQ801/Q802/Q804/
Q811or /Q812
Check Q809Q801/Q802/Q811/Q812
Change PT801
37
Q805
NG
Replace IC801