Power/Inverter Board - HP L1702 Service Manual

9.2.2 Power Board
No Power
Check CON102 Pin12 =12V, Pin3,4=5V
OK
Check AC line volt 110V or 220V
OK
Check the voltage of C904(+)
OK
Check start voltage for the pin3 of IC901
OK
Check the auxiliary voltage is bigger than 10V and smaller than 20V
OK
CheckIC901 Pin8 PWM wave
OK
Check Q903,R917,D910,D911,ZD904
NG
NG
NG
NG
NG
NG
30
Check AC line
Check bridge rectified circuit and F901circuit
Check R906, R907 and change IC901
1) Check IC901
2) Check ZD901,Q901,Q902...OVP circuit
Check IC901
HP L1702