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22. IMAGE QUALITY PROBLEM
Field Service Ver. 2.0 Jul. 2009
896
TROUBLESHOOTING
22.3.32
Printer 4-color: poor color reproduction
A. Typical faulty images
B. Troubleshooting procedure
A02EF4C527DA
Step
Section
Check item
Result
Action
1
Paper
Paper is damp.
YES
Change paper to one just
unwrapped from its package.
2
Transfer belt unit Terminal is dirty.
YES
Clean.
3
Transfer roller
unit
Transfer roller is installed properly.
NO
Reinstall.
4
Charge neutralizing needle is not
separated and ground terminal is
connected properly.
NO
Correct or change.
5
IDC sensor
Sensor is dirty.
YES
Clean IDC sensor and execute
the image stabilization.
6
Image Process
Adjustment
o
Gradation
Adjust
(Service Mode)
“Conv. Value” falls within the
specified range as checked through
gradation adjust.
Dark: 0 ± 100
Highlight: 0 ± 60
YES
Go to step 9.
7
Image Process
Adjustment
o
D Max Density
(Service Mode)
The problem has been eliminated
through the adjust of D Max Den-
sity.
NO
Go to next step.
8
Image Process
Adjustment
o
Stabilizer
o
Reset + Stabi-
lizer
(Service Mode)
After the Reset + Stabilizer
sequence has been completed, run
gradation adjust.
NO
Go to next step.
9
The problem has been eliminated
through the checks of steps up to 8.
NO
Change transfer belt unit.
o
Change printer control board
o
Change high voltage unit/2.
Service Manual Y110571-1
Summary of Contents for d-color MF651
Page 1: ...d Color MF651 d Color MF551 d Color MF451 Color Printer SERVICE MANUAL Code Y110571 1...
Page 24: ...MEASURES TO TAKE IN CASE OF AN ACCIDENT S 22 Blank Page...
Page 27: ...d Color MF651 d Color MF551 d Color MF451 Color Printer SERVICE MANUAL Code Y110571 1...
Page 1053: ...UPDATING STATUS DATE UPDATED PAGES PAGES CODE 10 2009 1ST EDITION 1053053 Y110571 1...