Canon PC430 - The Copy Has Uneven Density (Darker at Front); The Copy Has Uneven Density (Lighter at Front)

COPYRIGHT © 1998 CANON INC. CANON PC400/420/430,FC200/220 REV.0 JAN.1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
10-18
CHAPTER 10 TROUBLESHOOTING
4. The copy has uneven density (darker at front).
5. The copy has uneven density (lighter at front).
6. The copy is foggy (overall).
Cause Step Checks YES/NO Remedies
Scanner 1 Clean the scanning lamp,
reflecting plate, and lens.
Is the problem corrected?
YES End.
Cartridge, Scanning
lamp
2 Press the Copy Start key, and
switch the copier OFF in the
middle of operation; then, open
the top cover.
Does the toner image on the
photosensitive drum before
transfer have uneven density?
YES 1. Replace the cartridge.
2. Replace the scanning
lamp unit.
Transfer charging roller NO Check the transfer charg-
ing roller.
Cause Step Checks YES/NO Remedies
Scanner 1 Clean the scanning lamp,
reflecting plate, and lens.
Is the problem corrected?
YES End.
Scanning lamp,
Developing bias
2 Is continuity present between
photosensitive drum PCB and
grounding spring?
YES 1. Check if the scanning
lamp goes ON normally.
2. Check the developing
bias.
Grounding spring NO Check to make sure if the
grounding spring is prop-
erly attached in front of the
cartridge.