Canon NP6621, Service Handbook

Page: 59 / 146

3–13
IMAGE FAULTS
Yes/No
NO
YES
YES
YES
YES
YES
NO
YES
NO
Cause
Transfer
charging
roller
Drum
cartridge
Drum clean-
ing assembly
(drum
cartridge)
Fixing
assembly
Step
1
2
3
4
5
6
7
Checks
Turn OFF the power switch while copy
paper is moving through the feeding
assembly. Is the back of the copy
soiled at this time?
Execute service mode No. 403
(transfer roller cleaning). Is the prob-
lem corrected?
Make several blank copies. Is the
problem corrected?
Is the transfer charging roller exces-
sively soiled?
Is the soiling on the back horizontal at
intervals of about 4.2 cm?
Is the soiling vertical at intervals of
about 1.6 cm?
Is the upper fixing roller or the lower
fixing roller dirty?
13 The back of the copy is soiled.
Remedy
Go to step 7.
End.
End.
Replace the transfer charg-
ing roller.
1. Clean the registration
roller and the transfer
guide plate.
2. Check the drum cartridge
for leakage of toner.
1. Clean the manual feed
feeding roller.
2. Check the drum cartridge
for leakage of toner.
1. Clean the feeding assem-
bly.
2. Check the drum cartridge
for leakage of toner.
1. Clean the upper and
lower fixing pressure
roller.
2. Check if the oiling roller is
soiled with toner, if the
roller is very dirty, replace
it.
Clean the delivery roller and
the fixing assembly paper
guide plate.