Power/Inverter Board - HP L1902 Service Manual

9.2.2 Inverter / Power Board
1.) No power
Check to CN902 Pin1
And Pin3=5V
Check AC line volt 120V
or 220V
Check the voltage of C905(+)
Check start voltage for the pin3 & pin7 of IC901
Check the auxiliary voltage Is smaller than20V
Check D910,D911, ZD902,R925,R926,R927
NG
OK
NG
NG
OK
OK NG
OK NG
OK NG
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Check Interface board
Check F901, Check BD901,Q901,IC901
Check bridge rectified circuit
Check IC901
1) Check IC902,IC903
2) Check Q902,Q903...OVP circuit
HP L1902 Service Manual