Back Marking - Konica Minolta magicolor 4690MF Service Manual

19. Image quality problems
19.1.16

Back marking

A. Typical faulty images
B. Troubleshooting procedure
Step Section
1 Paper path
2
Fuser unit
3
4
Transfer belt unit
5
6
312
Check item
Is there a foreign matter on the
paper path?
Is the fusing entrance guide plate
dirty or scratched?
Is the fusing roller scratched or
dirty?
Is the transfer belt dirty with fin-
gerprints, oil, or other foreign mat-
ter?
Is the transfer roller dirty or
scratched?
Has the problem been eliminated
through the checks of steps up to
5?
Field Service Ver. 1.0 May 2008
Result Action
YES Remove the foreign matter.
YES Clean or change.
YES Change the fuser unit.
YES Clean.
YES Change the transfer roller.
Change the transfer belt unit.
Change the fuser unit.
NO
Change the high voltage unit/1.
Change the high voltage unit/2.
A0CRF4C518DA