COPYRIGHT © 1998 CANON INC. CANON NP7161/NP7160 REV.0 AUG. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 10 TROUBLESHOOTING10–3512. The copy has white spots. (vertical)DevelopingassemblyPhotosensitive drumCopy paperScanner rail,Scanner cableCharging wire1234Is the problem noted at intervals ofabout 3.2 cm? (scratch on thedeveloping cylinder)Is the problem noted at intervals ofabout 9.4 cm? (scratch on thephotosensitive drum)Try copy paper fresh out of package.Is the problem corrected?Is the problem noted at the samelocation on all copies?1. Clean the developing roller.2. Clean the surface of the developingcylinder.3. If scratches are found on thesurface of the developing cylinder,replace the developing cylinder orthe developing assembly.1. Clean the photosensitive drum.2. If the scratches are found on thephotosensitive drum, replace thedrum unit.The copy paper is moist. Instruct theuser on the correct method of storingcopy paper.1. Check the scanner rail for a foreignobject.2. Adjust the tension of the scannercable.Clean each charging wire.ActionsCause ChecksYESYESYESYESNOStep Yes/No
