Printer 4-Color: Poor Color Reproduction - Konica Minolta bizhub C650 Service Manual

Field Service Ver. 8.0 Jun. 2008
18.3.32

Printer 4-color: poor color reproduction

A. Typical faulty images
B. Troubleshooting procedure
Step Section
Paper
1
2 Transfer belt unit Terminal is dirty.
3 Transfer roller
unit
4
IDC sensor
5
Image Process
Adjustment
→ Gradation
6
Adjust
(Service Mode)
Image Process
Adjustment
7
→D Max Density
(Service Mode)
Image Process
Adjustment
→ Stabilizer →
8
Reset + Stabi-
lizer
(Service Mode)
9
Check item
Paper is damp.
Transfer roller is installed properly.
Transfer roller is dirty or scratched.
Sensor is dirty.
"Conv. Value" falls within the
specified range as checked through
gradation adjust.
Dark: 0 ± 100
Highlight: 0 ± 60
The problem has been eliminated
through the adjust of D Max Den-
sity.
After the Reset + Stabilizer
sequence has been completed, run
gradation adjust.
The problem has been eliminated
through the checks of steps up to 8.
18. Image quality problem
4036fs4058c0
Result
YES Change paper to one just
unwrapped from its package.
YES Clean.
NO Reinstall.
NO Change transfer roller unit.
YES Clean IDC sensor and execute
the image stabilization.
YES Go to step 9.
NO Go to next step.
NO Go to next step.
NO Change transfer belt unit.
→ Change printer control board
→ Change high voltage unit/2.
Action
727