The Copy Has Poor Sharpness - Canon NP6330 Service Manual

CHAPTER 11 TROUBLESHOOTING
20

The copy has poor sharpness.

Step
Cause
1
Original
2
Copyboard
glass
3
Lens drive
assembly
4
Mirror
Scanner
5
Transfer
charging
assembly
6
7
Developing
assembly
Developing bias 8
11-70
Checks
Is the original off the copyboard
glass?
Is the copyboard glass soiled with
oil?
Is the copyboard glass installed
properly?
Turn off and then on the power
switch. Does the lens move
smoothly?
Is the horizontal reproduction ratio
in Direct within specification?
Is the transfer charging assembly
set securely?
Is the charging wire of the transfer
charging assembly hooked
properly, and is its height normal?
Is the developing assembly set
securely? (Check to make sure
that the rolls of the developing
assembly are in firm contact with
the photosensitive drum.)
Is the developing bias generated
normally?
COPYRIGHT © 1997 CANON INC.
YES/NO
YES
YES
NO
NO
YES
NO
NO
NO
NO
CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
1. Check the copyboard
cover for warping.
2. Advise the user on
how to place an
original.
• Clean the copyboard
glass.
• Install the copyboard
glass.
Check the lens drive
assembly.
Re-route the scanner
drive cable.
Clean the scanning
lamp, reflecting plate,
mirror, lens, and dust-
proofing glass.
Set the charging
assembly securely.
Re-string the charging
wire.
Re-set the developing
assembly.
1. Replace the high-
voltage power supply
PCB.
2. Replace the DC
controller PCB.