Printer Monocolor: Uneven Density In Main Scan Direction - Konica Minolta bizhub C450 Service Manual

18. Image quality problem
18.3.16

Printer Monocolor: uneven density in main scan direction

A. Typical Faulty Images
B. Troubleshooting Procedure
Step Section
Imaging Unit
1
2
LPH Assy
3
Image check
4
Image Transfer
5
Belt Unit
6
7
394
4036fs4046c0
Check Item
The surface of the PC Drum is
scratched.
Dirty on the outside.
The surface of the lens array is
dirty.
Monocolor uneven image (uneven
high density) occurs.
Image Transfer Belt Unit makes
positive contact with plates on rails.
Cam gear operates properly.
The problem has been eliminated
through the checks of steps up to 6.
Field Service Ver. 1.0 Mar. 2005
4036fs4047c0
Result Action
YES Change Imaging Unit.
YES Clean.
YES Clean with cleaning jig.
YES Select "Service Mode" →
"Machine" → "LPH Rank" and run
"LPH Rank."
NO Check and correct contacts.
NO Change Image Transfer Belt Unit.
NO Change Imaging Unit.
→ Change Image Transfer Belt
Unit.
→ Change High Voltage Unit/2
(Developing Bias).
→ Change High Voltage Unit/1
(Image Transfer, Neutralizing).