Printer 4-Color: White Lines, White Bands, Colored Lines And Colored Bands In Sub Scan Direction - Konica Minolta bizhub C25 Service Manual

22. IMAGE QUALITY PROBLEM
22.2.24 Printer 4-color: white lines, white bands, colored lines and colored bands
in sub scan direction
A. Typical faulty images
White lines
B. Troubleshooting procedure
Step Section
1 Image check
2 Transfer belt unit Fingerprints, oil, or other foreign
3
4
5 Transfer roller
unit
6 Paper path
7
8 Fuser unit
9
10
368
White bands
Check item
A white line or colored line in sub
scan direction.
matter is evident on the transfer belt.
Transfer belt is dirty or scratched.
Cleaning blade is not effective in
removing toner completely.
Transfer roller is dirty or scratched.
There is foreign matter on paper
path.
Image transfer paper separator
fingers are damaged or dirty.
Fusing entrance guide plate is dirty
or damaged.
Fusing paper separator fingers are
dirty.
The problem has been eliminated
through the checks of steps up to 9.
Field Service Ver. 1.1 May 2011
Colored lines Colored bands
Result
YES Clean the comb electrode.
YES Clean with specified solvent.
(See Maintenance.)
YES Clean dirty belt with a soft cloth.
Change transfer belt unit if belt is
damaged.
YES Change transfer belt unit.
YES Change transfer roller unit.
YES Remove foreign matter.
YES Clean or change.
YES Clean.
Change fuser unit.
YES Clean.
NO Change printer control board
A02EF4C507DA
Action