Troubleshooting Of Image Faults - Canon NP6317 Service Handbook

C.

TROUBLESHOOTING OF IMAGE FAULTS

1. Light image (halftone areas only)
Cause/Problem
Procedure
area
1
AE adjust- 2
ment
Black devel- 3
oping assem-
bly
Lens, dust- 4
proofing glass
Photosensitive
drum
Check
Does the image quality improve after the
basic adjustment procedure is followed?
Is the image lighter is when a copy is
made using AE?
Is the image lighter when a copy is made
using a black developing assembly?
Is the image quality improved after the
lens, dust proofing glass, and mirror are
cleaned?
CHAPTER 4 IMAGE TROUBLESHOOTING
Result
Yes
Yes
Yes
Yes
No
Action
End.
Perform AE adjustment.
Check that J39-1 and
J39-4 of the black devel-
oping assembly are con-
nected by a jumper wire.
If they are not, connect
them.
End.
Replace the drum unit.
4-5