11-64CHAPTER 11 TROUBLESHOOTINGCOPYRIGHT © 1997 CANON INC. CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)12 The copy has white spots. (horizontal)CauseBlank exposureassemblyOutside lightChecksDoes the blank shutter solenoidoperate where white spots orwhite lines occur in the copyimage while the scanner is movingforward?Is the photosensitive drumexposed to light from outside?Step89YES/NONOYESActionCheck the blankexposure assembly.Find out the cause of theinfiltration of light.CauseDevelopingassemblyPhotosensitivedrumCopy paperScanner rail,scanner cableCharging wireChecksIs the problem noted at intervalsof about 3.3 cm? (scratches onthe developing cylinder)Execute “408” in service mode [4].Is the problem corrected?Is the problem noted at intervalsof about 9.4 cm? (scratches onthe photosensitive drum)Try fresh copy paper.Is the problem corrected?Is the problem noted at the samelocation on all copies?Step12345YES/NOYESYESYESYESYESNOAction1. Clean the developingrolls.2. Clean the surface ofthe developingcylinder.3. If scratches arefound on the surfaceof the developingcylinder, replace thedeveloping cylinder.End.1. Clean the drum.2. If scratches arefound on the drum,replace the drumunit. (Be sure to findout the cause of thescratches.)The copy paper may bemoist; advise the useron the correct method ofstorage.1. Check the scannerrail for foreign matter.2. Adjust the tension ofthe scanner cable.Clean each chargingwire. If the dirt cannot beremoved, replace thecharging wire.Download Service Manual And Resetter Printer at http://printer1.blogspot.com
