AOC LM725 - Page 35

AOC LM725
35
2.) No Backlight
Check CN102 pin12 =12V
NG
OK
Check adapter
Check ON/OFF signal
Check Interface board or main board
NG
OK
Check U201 pin9=12V
NG
OK
Change Q201 or Q202
Check U201 PIN10,7 have the output of sawtooth wave at short time
NG
OK
Change U201
Check D201(-), D202(-) have the output of square wave at short time.
NG
OK
Check Q205, Q206, Q207, Q208, Q203, Q204
Check the resonant wave of pin2 & pin5 for PT201, PT202
NG
Check the output of PT201, PT202
Check Q209, Q210, Q211, Q212
Check connecter & lamp
OK
NG
Change PT201, PT202
OK