Canon NP6251 Service Manual page 608

Cause Step
Transfer/
separation
charging
assembly,
Pre-transfer
charging
assembly
Blanking
exposure lamp,
DC controller
PCB
External light
COPYRIGHT © 1997 CANON INC.
Checks
6 Are the separation claws of the
cleaner assembly in contact with
copy paper while the copy paper
is being fed?
7 Are the blank exposure LEDs
(lamp) corresponding to the
problem in the copy image ON
while the scanner is moving
forward?
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
YES/NO Action
YES 1. Clean the pre-transfer
charging assembly
and the
transfer/separation
charging assembly. If
the dirt cannot be
removed, replace the
charging wire.
2. Try replacing the copy
paper.
3. Select 'FUZZY' in ser-
vice mode (
and set it to '3'.
YES Check the wiring from
the blanking exposure
lamp to the DC controller
PCB; if normal, replace
the DC controller PCB.
NO Check the
photosensitive drum to
see if it should not be
exposed to external light.
),
5
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