Canon iR105 Series, Service Manual

Page: 412 / 1029

CHAPTER 6 TROUBLESHOOTING
6-80
COPYRIGHT© 2001 CANON INC. 2000 2000 2000 2000 CANON iR105 REV.0 JULY 2001
3.3.12 The output has white spots (horizontal)
Developing assembly
1) Does the problem occur at intervals of about 79 mm?
YES: [1] Clean the developing rolls.
[2] Dry wipe the surface of the developing cylinder.
[3] If the site of installation is at a high elevation, electrical leak-
age is a possibility between the developing cylinder and the
drum. Try switching DIPSW from UP to DOWN on the high-
voltage PCB (rear of the machine). This, however, lowers den-
sity.
[4] If there is a scratch on the surface of the developing cylinder,
replace the developing cylinder.
Drum
2) Does the problem occur at intervals of about 340 mm?
YES: [1] Clean the drum (especially, where the developing rolls are in
contact on both ends).
[2] If there is a scratch on the surface of the drum, replace the
drum.
Copy paper
3) Try paper fresh out of package. Is the problem corrected?
YES: The copy paper is moist. Advise the user on the place of storage
and the method of storage.
Scanner rail, Scanner cable
4) Does the problem occur only in copy images?
YES: [1] Check the scanner cable for foreign matter.
[2] Adjust the scanner cable for tension.
Charging wire (dirt), Photosensitive drum
5) Clean the charging wire. Is the problem corrected?
YES: End.
6) Is there a scratch on the surface of the photosensitive drum?
NO: Clean the charging assemblies.
YES: Replace the photosensitive drum.