Canon Vizcam 1000, Service Manual

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COPYRIGHT © 2001 CANON INC. CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
7. TROUBLESHOOTING IMAGE FAULTS/MALFUNCTIONS
10 The copy has white spots.
Cause
Developing
assembly
Photosensitive
drum, Transfer
belt
Fixing roller
Waste toner
(caking)
Developer
(caking)
Step
1
2
3
4
5
Checks
Is there a small lump of toner in the
middle of a spot?
Generate a halftone test print
(PGTYPE=5). Is the problem noted?
If all colors, go to step 4.
If a specific color, go to the next step.
• Check the photosensitive drum
and the transfer belt for scratches.
• Check the transfer belt for
scratches and deformation.
Is the problem noted at intervals of
about 180 mm?
Check to find out whether the lump of
toner is of waste toner or developer.
• Waste toner: gray (mixed colors)
• Developer: Y, M, C, or Bk
Yes/No
YES
NO
YES
YES
YES
NO
Action
Go to step 5.
Check the developing
assembly and the devel-
oping cylinder for which
the problem is noted; if a
fault is found, clean or
replace it.
Replace the photosensi-
tive drum or the transfer
drum belt.
Check the fixing roller for
scratches and deforma-
tion.
Check the end seal of the
photosensitive drum
cleaner blade.
Check the end of the
cylinder of the developing
assembly for dirt.
• Replace the developer.
• Replace the developing
assembly.