Olivetti d-color MF651, Service Manual, Page: 943 / 1053

Field Service Ver. 2.0 Jul. 2009 22. IMAGE QUALITY PROBLEM
883
TROUBLESHOOTING
22.3.20 Printer monocolor: gradation reproduction failure
A. Typical faulty images
B. Troubleshooting procedure
A02EF4C522DA
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 Photo/density Original type and screen pattern are
selected properly. NO Change screen pattern.
3 Imaging unit Dirty on the outside. YES Clean.
4 PH unit The surface of the PH window is
dirty. YES Clean with cleaning jig.
5 State Confirma-
tion
o Level His-
tory 1
(Service Mode)
IDC output value is around 4.3 V. NO Clean IDC sensor and execute
the image stabilization.
Check image transfer belt for
damage and correct as neces-
sary.
6 Image Process
Adjustment
o Gradation
Adjust
(Service Mode)
“Conv. Value” falls within the
specified range as checked through
gradation adjust.
Dark: 0 ± 100
Highlight: 0 ± 60 YES Go to step 9.
7 Image Process
Adjustment
o
D Max Density
(Service Mode)
The problem has been eliminated
through the adjust of D Max. NO Go to next step.
8 Image Process
Adjustment
o
Stabilizer
o
Init Image
Stabilization
(Service Mode)
After the Init Image Stabiliza-
tion sequence has been completed,
run gradation adjust; NO Go to next step.
9 The problem has been eliminated
through the checks of steps up to 8. NO Change imaging unit.
o
Change printer control board
o
Change PH unit.
o Change high voltage unit/2.
Y110571-1 Service Manual