The Copy Has White Spot (Vertical); The Copy Has White Lines (Vertical) - Canon NP6218 Service Manual

10. The copy has white spot (vertical).

11. The copy has white lines (vertical).

Cause Step
Fixing
assembly
Primary
charging roller
Transfer
charging roller
Static
eliminator
Developing
assembly
Copy paper
Photosensitive
drum
Light from
outside
COPYRIGHT © 1997 CANON INC.
Checks
1 Make a copy with the copyboard
cover lifted, and turn off the power
switch while the paper is moving
through the feeding assembly. Are
white spots or liens noted on the
copy before it moves through the
fixing assembly?
2 Execute 'No. 402' in service mode
(primary charging roller cleaning).
Is the problem corrected?
Execute 'No. 409' in service mode
3
(transfer roller cleaning). Is the
problem corrected?
4 Is dirt, cracks, or scratches noted
on the transfer charging roller?
5 Are the position and condition of
the transfer charging roller
pressure spring normal?
6 Clean the static eliminator. Is the
problem corrected?
Is the developing cylinder coated
7
with a uniform layer of toner?
8 Try fresh copy paper. Is the
problem corrected?
9 Are there scratches around the
photosensitive drum?
CANON NP6218 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 10 TROUBLESHOOTING
Results Action
NO 1. Clean the inlet guide
(upper, lower) of the
fixing assembly.
2. Check the upper
fixing unit.
YES End.
YES End.
YES Replace the transfer
charging roller.
NO Correct or replace the
spring.
YES End.
NO
Take out the developing
assembly, and shake it
several times. If the
problem is not corrected,
replace the developing
assembly.
YES The copy paper may be
moist; advise the user
on the correct method of
storing paper.
YES Replace the drum
cartridge. (Be sure to
investigate the cause of
the scratches.)
NO Check if the photosensi-
tive drum is exposed to
light from outside.
10-55