Acer AT1945, Service Manual

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34
No Power (No LED indicator)
Check bridge rectified circuit and F901 circuit
Check R904, R905 and Change IC901
1) Check IC901,D902,C908
2) Check IC902 OVP circuit
Check CN902 pin10,11 = 12V
Check AC line volt 110V or 220V
Check AC input
Check the voltage of C905 (+)
Check start voltage for the pin8 of IC901
NG
Check the auxiliary voltage is bigger than
10V and smaller than 20V
OK
NG
Check T901, Q903, D906, D904, D912, ZD920, ZD902, IC903
Check IC901 pin5 PWM wave
OK
Check IC901
NG
NG
OK
NG
OK
OK