Konica Minolta bizhub C200 Service Manual page 375

19. Image quality problem
19.3.15 Printer monocolor: white lines in sub scan direction, white bands in sub
scan direction, colored lines colored bands in sub scan direction
A. Typical faulty images
White lines in sub
scan direction
B. Troubleshooting procedure
Step Section
Imaging unit The surface of the PC drum is
1
scratched.
2 Dirty on the outside.
Contact terminals make good con-
3 nection between each IU and
machine.
Developing bias contact terminal
4
makes good connection.
PH unit The surface of the PH window is
5
dirty.
The problem has been eliminated
6 through the checks of steps up to 5.
336
White bands in sub Colored lines in sub
scan direction
Check item
Field Service Ver. 1.0 Jun. 2008
Colored bands in sub
scan direction scan direction
Result Action
YES Change imaging unit.
YES Clean.
NO Clean contact terminals.
NO Clean contact terminal and check ter-
minal position.
YES Clean with cleaning jig.
NO Change imaging unit.
→ Change transfer belt unit.
→ Change PH unit.
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