20. The copy has poor sharpness.COPYRIGHT © 1997 CANON INC. CANON NP6218 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON) 10-61CHAPTER 10 TROUBLESHOOTINGCauseOriginalCopyboardglassLens driveassemblyTransfercharging rollerDrum cartridgeDevelopingassemblyDevelopmentbiasMirrorScannerChecksIs the original off the glasssurface?Is copyboard glass stained withoil? Is the copyboard glassattached correctly?Turn off and on the power switch.Does the lens move smoothly?Execute ‘No. 403’ in service mode(transfer roller cleaning). Is theproblem corrected?Is the transfer charging rollersecurely inserted?Is dirt, cracks, or scratches notedon the transfer charging roller?Are the position and condition ofthe transfer roller pressure springnormal?Is the drum cartridge securelyset? (Check if the spacer for thedeveloping assembly is in contactwith the photosensitive drumunder pressure.)Is the development bias generatednormally?Is the horizontal reproduction ratioin Direct with on specification?Step12345678910ResultsYESYESNOYESNOYESNONONONOYESAction1. Check the copyboardcover for warping.2. Advise the user howto place an original.• Clean the copyboardglass.• Re-attach thecopyboard glass.Check the lens driveassembly.End.Re-insert the chargingroller.Replace the transfercharging roller.Correct or replace thespring.Replace the drumcartridge or thedeveloping assembly.• Replace the compositepower supply PCB.(Replace the DC controller PCB.)Adjust the positionbetween No. 1 and No. 2mirrors.Clean the scanninglamp, reflecting plate,mirrors, lens, and dust-proofing glass.
