16. Image quality problem
Field Service Ver. 1.0 May 2006
222
magicolor 7450
T
roubleshooting
16.3.7
Monocolor: foggy background
A. Typical Faulty Images
B. Troubleshooting Procedure
4036fs4030c0
ABCD
ABCD
ABCD
ABCD
ABCD
Step
Section
Check Item
Result
Action
1
[SERVICE
MENU]
→
[DIAG-
NOSIS MENU]
→
[PRINT MENU]
→
[ELEMENT
PAGE]
Check data for Vg and Vb.
Color
Vdc: Around 400 V
Vg : Around 500 V
Black
Vdc: Around 400 V
Vg : Around 500 V
NO
Go to next step.
2
Check TCR data.
NO
Go to next step.
3
IDC output value is around 4.3 V.
NO
Clean IDC Sensor.
Check Transfer Belt for dam-
age.
4
Element data
check results
Low TCR and low Vg and Vdc
YES
Go to step 8.
5
Low TCR and high Vg and Vdc
YES
Go to step 11.
6
TCR falling within specified range
and low Vg and Vdc
YES
Go to step 8.
7
TCR falling within specified range
and high Vg and Vdc
YES
Go to step 11.
8
Imaging Unit
Dirty on the outside.
YES
Clean.
9
PH Unit
The surface of the PH Window is
dirty.
YES
Clean with cleaning jig.
10
TCR Sensor win-
dow
The color TCR Sensor window is
dirty.
YES
Clean.
11
[SERVICE MENU]
→
[ALIGNMENT]
→
[ELECTRIFICA-
TION]
The problem is eliminated after
ELECTRIFICATION has been
adjusted.
NO
Go to next step.
12
[SERVICE MENU]
→
[ALIGNMENT]
→
[MAXIMUM
DENSITY]
The problem has been eliminated
through the adjust of MAXIMUM
DENSITY.
NO
Go to next step.
13
The problem has been eliminated
through the checks of steps up to 12.
NO
Change Imaging Unit.
→
Change Controller Board
→
Change PH Unit.
→
Change High Voltage Unit
(Image Transfer, Neutralizing).
Summary of Contents for magicolor 7450
Page 1: ...SERVICE MANUAL 2006 05 2006 05 Ver 1 0 Ver 1 0 FIELD SERVICE magicolor 7450 magicolor 7450 ...
Page 3: ...ii Blank Page ...
Page 26: ...SERVICE MANUAL 2006 05 Ver 1 0 FIELD SERVICE Main Unit magicolor 7450 magicolor 7450 ...
Page 43: ...2 Product specifications Field Service Ver 1 0 May 2006 6 magicolor 7450 General Blank Page ...
Page 288: ...SERVICE MANUAL 2006 05 Ver 1 0 FIELD SERVICE Lower Feeder Unit ...
Page 317: ...3 Other Field Service Ver 1 0 May 2006 26 Lower Feeder Unit Maintenance Blank Page ...
Page 328: ...SERVICE MANUAL 2006 05 Ver 1 0 FIELD SERVICE Duplex Option ...
Page 333: ...1 Product specifications Field Service Ver 1 0 May 2006 2 Duplex Option General Blank Page ...
Page 345: ...6 Jam Display Field Service Ver 1 0 May 2006 14 Duplex Option Troubleshooting Blank Page ...