BenQ M2400HD Service Manual - Page 50

Power Board, No power

Page 50 highlights

24" LCD Color Monitor Power Board No power BenQ E2400HD Check CN902 PIN5.6 = 5V NG Check AC line volt 110V or 220V OK NG Check the voltage of C905 (+) OK NG Check AC input Check bridge rectified circuit and F901 circuit Check start voltage for the pin8 of IC901 NG OK Check R904, R905, Change IC901 Check the auxiliary voltage is bigger than 10V and smaller than 20V NG 1) Check IC901 OK 2) Check R909/D901/C908 circuit Check IC901 pin5 PWM wave OK NG Check IC901 Check D908/D906/D907/ZD921/ZD922/Q903/ZD902 50

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24” LCD Color Monitor
BenQ E2400HD
50
Power Board
No power
Check CN902 PIN5.6 = 5V
Check AC line volt 110V or 220V
Check AC input
Check the voltage of C905 (+)
Check bridge rectified circuit and F901 circuit
Check start voltage for the pin8 of IC901
Check R904, R905, Change IC901
NG
Check the auxiliary voltage is bigger than
10V and smaller than 20V
1) Check IC901
2) Check R909/D901/C908 circuit
OK
OK
NG
Check D908/D906/D907/ZD921/ZD922/Q903/ZD902
OK
Check IC901 pin5 PWM wave
OK
Check IC901
NG
NG
NG
OK
NG