COPYRIGHT © 1999 CANON INC. CANON NP6512/6612/7120/7130/7130F REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 11 TROUBLESHOOTING11-7420 The blanking lamp fails to turn on.YES/NONOYESCauseSide blank-ing PCBDC control-ler PCBStep1ChecksRemove J106 from the DC controlPCB, and set the meter range to 1 kΩ;then, connect the meter probes toJ106-1 and -2 on the harness side. Isthe meter reading about 20 Ω?ActionCheck the harness; ifnormal, replace theside blanking PCB.Replace the DCcontroller PCB.22 The scanning lamp fails to turn on.YES/NONONONOYESNOCauseScanninglampFuse (FU1)LampDC control-ler PCBCompositepowersupply PCBStep1234ChecksTurn off the power switch, and discon-nect the power plug from the poweroutlet.Is the scanning lamp (LA1) mountedcorrectly?Set the meter range to 1 kΩ, andconnect the meter probes to bothterminals of the fuse (FU1). Does theindex of the meter swing?Disconnect the connector J910 from thecomposite power supply PCB, and setthe tester range to 1kΩ.Does the tester index swing when theprobes are connected to J910-1 andJ910-3 on the lamp side?Replace the DC controller PCB. Is theproblem corrected?ActionMount the scanninglamp correctly.Replace the fuse(FU1).Check the cable fromthe composite powersupply PCB to thelamp; if normal,replace the lamp.End.Check the wiringbetween the DCcontroller PCB and thecomposite powersupply PCB; if nor-mal, replace thecomposite powersupply PCB.21 The pre-exposure lamp fails to turn on.YES/NONOYESCausePre-exposurelamp PCBDC control-ler PCBStep1ChecksRemove J121 from the DC controlPCB, and set the meter range to 1 kΩ;then, connect the meter probes toJ121-1 and -2 on the harness side. Isthe meter reading about 4 Ω?ActionCheck the harness; ifnormal, replace thepre-exposure lampPCB.Replace the DCcontroller PCB.
