Printer Monocolor: White Lines In Main Scan Direction, White Bands In Main; Scan Direction - Konica Minolta bizhub C250 Service Manual

Field Service Ver. 1.0 Jul. 2005
18.3.15

Printer Monocolor: white lines in Main Scan Direction, white bands in Main

Scan Direction, colored lines in Main Scan Direction, colored bands in
Main Scan Direction
A. Typical Faulty Images
White lines in Main

Scan Direction

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B. Troubleshooting Procedure
Step Section
Image check A white line or black line in sub
1
scan direction is sharp.
Imaging Unit The surface of the PC Drum is
2
scratched.
3 Dirty on the outside.
Contact terminals make good con-
4 nection between each IU and
machine.
Developing bias contact terminal
5
makes good connection.
PH Unit The surface of the PH Window is
6
dirty.
The problem has been eliminated
7 through the checks of steps up to 6.
White bands in Main Colored lines in Main
Scan Direction
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Check Item
18. Image quality problem
Colored bands in Main
Scan Direction
Scan Direction
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Result Action
NO Clean the Comb Electrode by moving
the Comb Electrode Cleaning Lever.
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 Image Transfer Belt Unit.
→ Change PH Unit.
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