19. Image quality problem
Field Service Ver. 1.0 Jun. 2008
340
T
roubleshooting
19.3.19
Printer monocolor: low image density
A. Typical faulty images
B. Troubleshooting procedure
A02EF4C516DA
ABCDE
ABCDE
ABCDE
ABCDE
ABCDE
Step
Section
Check item
Result
Action
1
Warning display
The maintenance call mark is
displayed on the panel.
YES
Take action according to the
warning code shown on the
state confirm screen.
2
State Confirma-
tion
o
Table Num-
ber
(Service Mode)
Check data for Vg and Vdc.
Color
Vdc: around 400 V
Vg : around 500 V
Black
Vdc: around 400 V
Vg : around 500 V
Go to next step.
3
State Confirma-
tion
o
Level His-
tory 1
(Service Mode)
Check TCR data.
(specified rang: 6 to 8 %)
NO
Go to next step.
4
IDC output value is around 4.3 V.
NO
Clean IDC sensor and exe-
cute the image stabilization.
Check image transfer belt for
damage and correct as nec-
essary.
5
Level history data
check results
Low TCR and low Vg and Vdc
YES
Go to step 10.
6
Low TCR and high Vg and Vdc
YES
Go to step 14.
7
TCR falling within specified range
and low Vg and Vdc
YES
Go to step 10.
8
TCR falling within specified range
and high Vg and Vdc
YES
Go to step 14.
9
The situations other than the above-
mentioned.
YES
Go to step 10.
10
Imaging unit
Dirty on the outside.
YES
Clean.
11
PH unit
The surface of the PH window is
dirty.
YES
Clean with cleaning jig.
12
Transfer belt unit
Transfer belt unit makes positive
contact with plates on rails.
NO
Check and correct contacts.
13
Is abnormality found in the cam
gear?
YES
Change transfer belt unit.
d-Color MF201
Service Manual Y109660-1