Canon NP6320 Service Manual page 212

CHAPTER 10 TROUBLESHOOTING
13. Toner marks on back of copy paper
Cause Step
1
Developing 2
assembly
Fixing assem- 3
bly
14. Faulty fixing
Cause Step
Upper and 1
lower devel-
oping rollers
Fixing roller 2
heater (H1)
Lower fixing 3
roller pressure
Copy paper
10-34
COPYRIGHT © 1999 CANON INC.
Checks
Press the Copy Start key, and switch the
copier OFF while the copy paper is on the
feeder.
Are there any toner marks on the back of
the copy paper?
Do the toner marks occur at intervals of
approx. 50mm?
Are the upper and lower fixing rollers
dirty?
Checks
Is faulty fixing occurring in the feed direc-
tion of the paper?
Does the fixing roller heater (H1) go ON
immediately after the copier is switched
ON?
Is the nip width within the standard?
CANON NP6320 REV.0 DEC. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
YES/
Action
NO
NO Check from step 3.
YES 1. Clean the registration
rollers and transfer as-
sembly guide.
2. Check if toner is leak-
ing from the develop-
ing assembly.
YES 1. Clean the upper and
lower fixing rollers.
2. Check if the oiling
roller is soiled with
toner. If the dirt is ex-
cessive, replace it.
NO Clean the copy delivery
rollers, separation claws,
and fixing assembly pa-
per guide.
YES/
Action
NO
YES Check for scratches on
the upper and lower fix-
ing rollers.
NO Refer to the sub-section
"Fixing roller heater
does not operate."
NO Adjust the lower fixing
roller pressure.
YES Check if the recom-
mended paper is being
used. If the results are
satisfactory when the
recommended paper is
used, instruct the user to
use it.