Acer AL1516 Service Manual page 37

5. No Backlight
Check C201 (+) =12V
Check ON/OFF signal
Check U201 pin9=12V ?
OK
Check the pin1 of U201 have saw tooth wave
OK
Check D201 (-) has the output of square wave at short time.
OK
Check the resonant wave of pin2 & pin5 for PT201
OK
Check the output of PT201
OK
Check connecter & lamp
NG
OK
NG
OK
NG
NG
NG
NG
Change F902
Check Interface board
NG
Change Q201 or Q202
Change U201
Check Q203/Q205/Q207/D201
Check Q209/Q210/C213
Change PT201
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