Printer Monocolor: Foggy Background - Konica Minolta bizhub C650 Service Manual

Field Service Ver. 8.0 Jun. 2008
18.3.21

Printer monocolor: foggy background

A. Typical faulty images
B. Troubleshooting procedure
Step Section
Warning display
1
State Confirma-
tion → Table
2 Number
(Service Mode)
State Confirma-
3
tion → Level His-
tory 1
(Service Mode)
4
5 Level history data
check results
6
7
8
9
10 Imaging unit
PH unit
11
Image Process
Adjustment →
12 Background Volt-
age Margin
(Service Mode)
ABCD
ABCD
ABCD
ABCD
ABCD
Check item
The maintenance call mark is
displayed on the panel.
Check data for Vg and Vdc.
Color Vdc: around 400 V
Vg : around 500 V
Black Vdc: around 400 V
Vg : around 500 V
Check TCR data.
(specified rang: 6 to 8 %)
IDC output value is around 4.3 V.
Low TCR and low Vg and Vdc
Low TCR and high Vg and Vdc
TCR falling within specified range
and low Vg and Vdc
TCR falling within specified range
and high Vg and Vdc
The situations other than the above-
mentioned.
Dirty on the outside.
The surface of the PH window is
dirty.
The problem is eliminated after
background voltage margin has
been adjusted.
18. Image quality problem
4036fs4030c0
Result
YES Take action according to the
warning code shown on the
state confirm screen.
NO Go to next step.
NO Go to next step.
NO Clean IDC sensor and execute
the image stabilization.
Check image transfer belt for
damage and correct as neces-
sary.
YES Go to step 10.
YES Go to step 12.
YES Go to step 10.
YES Go to step 12.
YES Go to step 10.
YES Clean.
YES Clean with cleaning jig.
NO Go to next step.
Action
715