C. Troubleshooting Image Faults - Canon NP6251 Service Manual

C. Troubleshooting Image Faults

1. The copy is too light (halftone only).
Cause Step
Scanner
Developing
assembly
Developing
assembly
Lamp regulator
DC controller
PCB
COPYRIGHT © 1997 CANON INC.
Checks
1 Perform the Image Adjustment
Basic Procedure. Is the problem
corrected?
2 Clean the standard white plate,
mirror, lens, and dust-proofing
glass. Is the problem corrected?
3 Are the rolls of the developing
assembly in firm contact with the
drum during copying?
4 Is the developing cylinder coated
with an even layer of toner?
5 Replace the lamp regulator. Is the
problem corrected?
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
YES/NO Action
YES End.
YES End.
NO Check the developing
assembly locking lever.
NO Check the developing
assembly.
YES End.
NO Replace the DC
controller PCB.
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