Adelpia TGL2240A, Service Manual

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22” LCD Color Monitor Adelpia TGL2240A
35
8.2.2 Power Board
1) No power
Check CN902 PIN3, 4 = 5V
Check AC line voltage 110V or 220V
Check AC input
Check the voltage of C905 (+)
Check bridge rectified circuit and F901 circuit
Check start voltage for the pin3 of U901
Check R904, R905, R906, Change U901
NG
Check the auxiliary voltage is bigger than
10V and smaller than 20V
1) Check U901
2) Check R909/D901/C908/C907 circuit
OK
OK
NG
Check D906/D907/D908/IC903/ZD921/ZD922/Q903/ZD902
OK
Check U901 Pin8 PWM wave
OK
Check U901
NG
NG
NG OK
NG