Uneven Density 1 - Konica Minolta BIZHUB C3100P Service Manual

[1] [2]
[1] White line
[3] Color line
(2) Initial troubleshooting procedure
Step Section
1 AIDC PROCESS
2 Image check
(3) 1-color troubleshooting procedure
Step Section
1 Image check
2 Imaging unit
3
4
5
6 PH unit
7
(4) 4-color troubleshooting procedure
Step Section
1 Transfer belt unit
2
3 Transfer roller
4 Paper path
5
6 Fusing unit
7
8 Neutralizing brush
9

5.2.4 Uneven density 1

(1) Typical faulty images
The arrow in the exemplary image troubles indicates the paper feeding direction.
[3] [4]
Check item
Select [Service Mode] -> [SYSTEM 2] -> [AIDC
PROCESS] and the image trouble is eliminated.
• Select [Service Mode] -> [PRINT MENU] ->
[HALFTONE 64]. Load the tray with A4 paper. This
runs a print cycle for C, M, Y, and K in that order.
• Check the image after printing to determine which color
causes the abnormal image.
Check item for the faulty color
A white line or black line in main scan direction is sharp.
The surface of the PC drum is scratched.
Dirty on the outside.
Contact terminals make good connection between each
imaging unit and machine.
Developing bias contact terminal makes good connection.
The surface of the PH window is dirty.
The problem has been eliminated through the checks of
steps up to 6.
Check item
Fingerprints, oil, or other foreign matter is evident on the
transfer belt.
Transfer belt is dirty or scratched.
Transfer roller is dirty or scratched.
There is foreign matter on paper path.
Image transfer paper separator fingers are damaged or
dirty.
Fusing entrance guide plate is dirty or damaged.
Fusing paper separator fingers are dirty.
The resistance values between the neutralizing brush and
the ground terminal is not ∞.
The problem has been eliminated through the checks of
steps up to 8.
K TROUBLESHOOTING > 5. IMAGE QUALITY PROBLEM
[2] White band
[4] Color band
Result
1 to 3
colors
colors
Result
YES
YES
YES
Result
YES
YES
YES
YES
YES
YES
YES
K-27
Action
NO Go to the next step.
Go to 1-color troubleshooting
procedure.
4 Go to 4-color troubleshooting
procedure.
Action
NO Clean the electrostatic charger wire.
Replace the imaging unit.
Clean.
NO Clean contact terminals.
NO Clean contact terminal and check
terminal position.
Clean with cleaning jig.
NO • Replace the transfer belt unit.
• Replace the PH unit.
Action
Clean with specified solvent. (See
Maintenance.)
• Clean dirty belt with a soft cloth.
• Replace the transfer belt unit
is damaged.
Replace the transfer roller.
Remove foreign matter.
Clean or change.
• Clean.
• Replace the fusing unit.
Clean.
NO • Check the contact.
• Replace the neutralizing brush.
NO Replace the printer control board.
if belt