Canon ImageRunner 600 Service Manual page 575

A
COPYRIGHT © 2000 CANON INC. CANON imageRUNNER 600 REV.1 JAN. 2000 PRINTED IN U.S.A.
<Checking Fogging>
Check PG6 (blank).
NO
Is there fogging?
YES
Select
COPIER>DISPLAY>DPOT>VDM
in service mode.
Check the potential
Is the reading
NO
control system; if
of 'VDM' between
normal, replace the
432 and 452?
photosensitive drum.
YES
Select
COPIER>DISPLAY>DPOT>VL1M
in service mode.
Check the following; if
Is the
faulty, replace parts as
NO
reading of 'VL1M'
necessary.
between 62 and
[1] laser output
82?
[2] potential control system
YES
Decrease the setting of
ADJUST>DEVELOP>DE-OFST in
service mode.
• A lower setting will result in a
lower density (lighter image).
<Checking Halftone Density>
Check PG4 (halftone).
Compare
against Nos. 6 and 7
(halftone) of the Test Chart.
Is the density about
the same?
NO
Execute service mode as follows:
1) Change the setting of the following according to the table:
ADJUST>V-CONT>VD-OFST and ADJUST>V-CONT>VL-
OFST.
To make the
To make the
image lighter
image darker
Default
VD-OFST
-4 -3 -2 +2
0
VL-OFST
+4 +3 +2 0 -2
2) If the image density is not satisfactory after performing step
1), change the following according to the table:
ADJUST>DEVELOP>DE-OFST
To make the To make the
image lighter image darker
Default
DE-OFST
-40 -30 -20 0 +20 +30 +40
3 Checking the Printer Side (2/2)
YES
End.
+3 +4
-3 -4
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