Faint Image, Low Image Density (Id Lowering - Konica Minolta BIZHUB C3100P Service Manual

Step Section
2 AIDC PROCESS
3 Image check
(3) 1-color troubleshooting procedure
Step Section
1 Imaging unit
2
3 PH unit
4 Transfer roller
5 Transfer belt unit
6
7
(4) 4-color troubleshooting procedure
Step Section
1 Transfer belt unit
2
3
4 Transfer roller
5
6

5.2.6 Faint image, low image density (ID lowering)

(1) Typical faulty images
The arrow in the exemplary image troubles indicates the paper feeding direction.
(2) Initial troubleshooting procedure
Step Section
1 Damp paper
2 IDC sensor
3 AIDC PROCESS
4 Image check
Check item
Select [Service Mode] -> [SYSTEM 2] -> [AIDC
PROCESS] and the image trouble is eliminated.
• Select [Service Mode] -> [PRINT MENU] ->
[HALFTONE 64]. Load tray with A4 paper. This runs a
print cycle for C, M, Y, and K in that order.
• Check the image after printing and the abnormal image
occurs only with one color.
Check item for the faulty color
The surface of the PC drum is scratched.
Dirty on the outside.
The surface of the PH window is dirty.
Check that the spring does not come off during the
pressure operation of the transfer roller.
Transfer belt unit makes positive contact with plates on
rails.
Is abnormality found in the cam gear?
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.
Terminal is dirty.
Image transfer roller is installed properly.
Image transfer roller is dirty or scratched.
The problem has been eliminated through the checks of
steps up to 5.
Check item
Paper is damp.
• IDC sensor is dirty.
• IDC sensor cover does not operate properly.
Select [Service Mode] -> [SYSTEM 2] -> [AIDC
PROCESS] and the image trouble is eliminated.
• Select [Service Mode] -> [PRINT MENU] ->
[GRADATION]. Load tray with A4 paper. This runs a
print cycle of 4 colors on one sheet of paper.
• Check the image after printing to determine which color
causes the abnormal image.
K TROUBLESHOOTING > 5. IMAGE QUALITY PROBLEM
Result
YES
Result
YES
YES
YES
YES
Result
YES
YES
YES
YES
Result
YES
YES
1 to 3
colors
colors
K-29
Action
NO Go to the next step.
Go to 1-color troubleshooting
procedure.
NO Go to 4-color troubleshooting
procedure.
Action
Replace the imaging unit.
Clean.
Clean with cleaning jig.
NO • Correct.
• Replace the transfer roller.
NO Check and correct contacts.
Replace the transfer belt unit.
NO • Replace the PH unit.
• Replace the high voltage unit.
Action
Clean it with the tender cloth or paper
which is dusted with the toner.
• Clean dirty belt with a soft cloth.
• Replace the transfer belt unit
is damaged.
Clean.
NO Reinstall.
Replace the transfer roller.
NO • Replace the transfer belt unit.
• Replace the high voltage unit.
Action
Change paper to one just unwrapped
from its package.
• Clean.
• Clean or correct the IDC sensor
cover.
NO Go to the next step.
Go to 1-color troubleshooting
procedure.
4 Go to 4-color troubleshooting
procedure.
if belt