19" LCD Color Monitor COMPAQ W19Q
37
9.2.2 Power Board
1. No Power
Check to CN902 Pin1, 2 =12V and Pin3, 4 = 5 V
OK
Check Interface board
Check AC line volt 120V or 220V
Change F901, Check BD901, Q903, IC901
Check the voltage of C905(+)
Check bridge retified circuit
Check start voltage for the Pin6 of IC901
Change IC901
OK
Check the auxiliary voltage is smaller than 20V
OK
NG
No power
NG
NG
OK
NG
Repeating the start voltage
Check D908, D909, ZD903…
Check IC902,IC903
Check Q903…OLP circuit
NG
OK