Canon NP6251 Service Manual page 605

CHAPTER 11 TROUBLESHOOTING
7. The copy has vertical fogging.
8. The copy has black lines (vertical, fuzzy, thick).
Cause Step
Primary
charging
assembly
Scanner system
Pre-exposure
lamp
Developing
assembly
Fixing assem-
bly, Cleaner
assembly
11-74
COPYRIGHT © 1997 CANON INC.
Checks
1 Clean the charging wire, grid wire,
and shielding plate. Is the problem
corrected?
2 Clean the scanning lamp,
reflecting plate, side reflecting
plate, lens, mirror, dust-proofing
glass, and heat absorbing glass.
Is the problem corrected?
3 Clean the pre-exposure lamp. Is
the problem corrected?
4 Is the developing cylinder coated
with an even layer of toner?
YES/NO
YES
YES
YES
NO
YES
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
End.
End.
End.
Check and clean the
edge of the blade of the
developing assembly.
Check the fixing
assembly and the
cleaner assembly.