Troubleshooting Faulty Images - Canon NP6330 Service Manual

C. Troubleshooting Faulty Images
1 The copy is too light. (halftone only)
Step
Cause
1
AE adjustment 2
3
Developing
assembly
4
Developing
assembly
5
Scanner
Photosensitive
drum
6
Lamp regulator
High-voltage
cord, High-
voltage power
supply PCB,
DC controller
PCB
COPYRIGHT © 1997 CANON INC.
Checks
Perform the Image Adjustment
Basic Procedure. Is the problem
corrected?
Make a copy in AE mode. Is the
copy too light?
Are the rolls of the developing
assembly in firm contact with the
drum during copying operation?
Is the coating of toner on the
developing cylinder even?
Clean the standard white plate,
mirror, lens, and dust-proofing
glass. Is the problem corrected?
Replace the lamp regulator. Is the
problem corrected?
CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
YES/NO Action
YES End.
YES Execute AE adjustment.
NO Check the developing
assembly locking lever.
NO Check the developing
assembly.
YES End.
NO Replace the drum unit.
YES
End.
NO
1. Check the high-
voltage cord for
electrical continuity.
2. Check the high-
voltage power supply
PCB and the DC
controller PCB.
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