Printer 4-Color: Incorrect Color Image Registration - Konica Minolta bizhub C450 Service Manual

18. Image quality problem
18.3.33

Printer 4-Color: incorrect color image registration

A. Typical Faulty Images
B. Troubleshooting Procedure
Step Section
Warning display The maintenance call mark is dis-
1
Machine condi-
2 tion
LPH Assy
3
Image Transfer
4 Belt Unit
5
6
Imaging Unit
7
Image Transfer
8
Roller Unit
9
Machine
→ Fusing Trans-
10
port Speed
(Service Mode)
Machine
→ Color regis-
11 tration Adjust-
ment
(Service Mode)
12
414
AA
AA
Check Item
played on the panel.
Vibration is given to the machine
after main power switch has been
turned ON.
LED retracting lever is locked in
position.
Fingerprints, oil, or other foreign
matter is evident on the Image
Transfer Belt.
Image Transfer Belt is dirty or
scratched.
Drive coupling to the machine is
dirty.
The surface of the PC Drum is
scratched.
Image Transfer Roller is installed
properly.
Image Transfer Roller is dirty or
scratched.
Brush effect or blurred image
occurs.
Check the specific color in which
color shift occurs.
The problem has been eliminated
through the checks of steps up to 11.
Field Service Ver. 1.0 Mar. 2005
4036fs4032c0
Result
YES Take action according to the
warning code shown on the State
Confirm screen.
YES Turn OFF and ON Main Power
Switch.
NO Slide out the IU and reinstall.
YES Clean with specified solvent.
(See Maintenance.)
YES Clean dirty belt with a soft cloth.
Change Image Transfer Belt Unit
if belt is damaged.
YES Clean.
YES Change Imaging Unit.
NO Reinstall.
YES Change Image Transfer Roller
Unit.
YES Readjust Fusing Transport
Speed.
YES Perform "Color registration
Adjustment." If color shift is not
corrected even with a correction
of ± 1 dot, go to next step.
NO Change Image Transfer Roller Unit.
→ Change Image Transfer Belt
Unit.
→ Change MFP Control Board
Action