20" LCD Color Monitor HP 2009v
35
9.2.2 Power Board
No Power
Check AC line volt 110V or 220V
OK
Check AC line
Check the voltage of C905(+)
Check F901, bridge rectified circuit
Check start voltage for the pin8of U901
Check R904, R905, U901
Check the auxiliary voltage is bigger than 10V and smaller
than 20V
Check Q901,D906,D908,Q903,U903,D907,ZD902
OK
OK
No power
NG
NG
NG
Check U901, D901, D900
NG
OK
Check U901 pin5 PWM wave
OK
Check U901
NG