Canon NP6320 Service Manual page 214

CHAPTER 10 TROUBLESHOOTING
18. Blurred image
Cause Step
Scanner drive 1
cable
Scanner 2
system rail
Scanner drive 3
system
Photosensitive 4
drum
Developing 5
gear
Drum drive
system
19. Broad dark lines in cross feed direction
Cause Step
1
Scanning 2
lamp
Lamp regula-
tor
Black devel- 3
oping unit
Scanner 4
blurring
Paper feeder
blurring
10-36
COPYRIGHT © 1999 CANON INC.
Checks
Does the cable overlap as it winds around
the drive capstan while the scanner is
moving? Is the tension of the cable alter-
nately too slack and too tight?
Does the scanner move smoothly when it
is pushed gently by hand?
Is the gear of the scanner drive system
missing?
Does the blurring occur at intervals of
approx. 95mm?
Does the blurring occur at intervals of
approx. 63mm?
Checks
Are the dark lines always in the same posi-
tion when Direct copies are made?
Does the scanning lamp flicker when the
scanner is moving forward?
Is there any difference in the broad dark
lines on a black copy compared with on a
color copy?
Does the position of the dark lines change
on a Reduce copy as compared with a Di-
rect copy?
CANON NP6320 REV.0 DEC. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
YES/
Action
NO
YES 1. Re-tension the cable.
2. Replace the drive
cable if it is twisted or
frayed.
NO Clean the scanner rails
with alcohol; then, apply
a small quantity of low-
viscosity lubricating oil.
YES Replace the gear.
YES 1. Check the drum drive
gear.
2. Check the ends of the
drum (where the
spacer rollers contact
it) for scratches or pro-
jections.
YES Check the developing as-
sembly.
NO Check the drum drive
unit.
YES/
Action
NO
YES Check from step 4.
YES Check the scanning lamp
and lamp regulator.
YES Check the toner coating
on the developing cylin-
der of the developing as-
sembly in which the
problem occurs.
YES Check the scanner.
NO Check the paper feeder.