COPYRIGHT © 1999 CANON INC. CANON imageRUNNER 400/330 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
14-41
CHAPTER 14 TROUBLESHOOTING
Cause
Development
Action
Set the developing
assembly correctly.
Check the developing
assembly.
Check the developing
bias.
Step
11
Yes/No
YES
NO
Check
Is the developing assembly firmly
locked to the photosensitive drum?
(check if the rolls of the developing
assembly are in firm contact with
the photosensitive drum.)
Cause
Developing
assembly
Scanner
Pre-exposure
lamp
Developing
assembly
Fluorescent lamp
Shading
Drum cartridge
Action
Check the developing
assembly locking unit..
End.
1.Replace the pre-
exposure lamp.
2.Replace the DC
controller PCB.
1.Clean the tip of the
blade of the
developing assembly.
(dry wiping)
2.Clean the surface of
the developing
cylinder.
3.Check to make sure
that the toner inside
the developing
assembly is not
uneven.
Replace the scanning
lamp.
Replace the drum unit.
Execute shading
correction once gain
(FUNCTION>CCD
>
MAN-ADJ
).
Step
1
2
3
4
5
6
Yes/No
NO
YES
NO
NO
YES
YES
NO
Check
Are the developing assembly rolls in
firm contact with the photosensitive
drum?
Clean the scanning lamp, reflecting
plate, mirror, lens, and dust-
proofing glass. Is the problem
corrected?
Does the pre-exposure lamp remain
on during copying operation?
Is the developing cylinder coated
with an even layer of toner?
Has the fluorescent lamp
blackened?
Is the halftone area of the PG
output uneven?
4
The copy has uneven density (darker at front).
5
The copy has uneven density (lighter at front).