Canon imageRUNNER 5065 series, Service Manual

Page: 418 / 596

Chapter 14
14-4
F-14-4
F-14-5
14.1.4 Making Checks on the Reader Unit
0015-5283
iR5065 / iR 5055 / iR5075 / / /
B
Is the density
too low or too high (too
light or too dark)?
Are the
readings ± 6 V of the
target value?
(*1)
Adjust the offset of the VD target potential.
< Checking the Solid Black Density >
YES
NO
NO
YES
NO
YES
Generate a solid black print.
Check the following readings (VL1 target value) in service mode:
COPIER>DISPLAY>DPOT>VL1M (for copier image)
COPIER>DISPLAY>DPOT>VL1M-P (for printer image)
Check the following readings (VD target value) in service mode:
COPIER>DISPLAY>DPOT>VDM (for copier image)
COPIER>DISPLAY>DPOT>VDM-P (for printer image)
Check the following, and replace them if
necessary:
1. Laser (for output)
2. Potential control system
3. Photosensitive drum
Check the primary charging
system; if normal, replace the
photosensitive drum.
Are the
readings ± 6 V of the
target value?
(*2)
C
D
<Checking the Halftone Density>
Generate a halftone image.
End.
To check a copier image,
See if No. 6 and No. 7 (halftone) of the Test Chart is
reproduced to the more or less the same density.
To check a printer (PDL) image,
See if the density of the halftone area represents the
original data properly.
Is the halftone
density optimum?
NO
YES
Adjusting the Offset Value of the VD Target Potential
(VD-OFFSET/VD-OFFSET-P)
COPIER>ADJUST>V-CONT>VD-OFST (for copier image)
COPIER>ADJUST>V-CONT>VD-VD-OFST-P (for printer image)
Default
Lighter image Darker image
-5 -4 -3 -2 -1 0 +1 +2 +3 +4 +5
C
D