Canon CLC 1120 Service Manual page 618

17 The copy has uneven density (A3, center).
Cause
------------
Photosensitive
drum shaft
Transfer drum
assembly
Attraction push-
on roller unit
COPYRIGHT © 1999 CANON INC.
Step
1 Generate a halftone test print using
TYPE=5 (DENS-M/C/Y/K=25,
TXPH=0), and make checks.
2 Is the screw on the core fixing tab
of the photosensitive drum loose?
3 Is the fixing screw on the flywheel
loose?
4 Is the flywheel mounted at an
angle?
5 Is the 300T gear of the transfer
drum soiled or damaged?
6 Is there deformation, damage or
caking of toner on the positioning
rubber ring (FB2-0524), transfer
drum sheet connecting plate,
transfer drum frame, or transfer
sheet?
7 Is there deformation on the transfer
blade/attraction brush?
8 Is the end of the transfer ring (FB2-
0584) bent?
9 Is there deformation/warping on
the attraction push-on roll unit?
10 Is the attraction roller moved/
rotated smoothly?
CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 13 TROUBLESHOOTING
Checks Yes/No Action
YES Tighten the screw.
YES Tighten the fixing screw.
YES Mount the flywheel
properly.
YES Clean or replace the
transfer drum assembly.
YES Clean or replace the
part.
YES Replace the part.
YES Replace the part.
YES Mount the part properly,
or replace it.
NO Replace the roller.
YES Check the scraper for
deformation; if
necessary, replace it.
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