Making Checks On The Printer Unit (2/2) - Canon iR6570 series Service Manual

A

13.1.3 Making Checks on the Printer Unit (2/2)

<Checking fro Fogging>
Generate a blank print.
NO
Is it foggy?
YES
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)
Are the readings ± 6 V
of the target value?
(*1)
YES
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)
NO
Are the readings ± 6 V
of the target value?
(*2)
YES
Adjusting the Offset of the VL Target Potential
(DE-OFFSET/DE-OFFSET-P)
Vary the value using the following as a guide:
COPIER>ADJUST>V-CONT>DE-OFST (for copier image)
COPIER>ADJUST>V-CONT>DE-OFST-P (for printer image)
Lighter image
-50 -40 -30 -20
F-13-3
B
Check the primary charging
NO
system and the potential control
system; if normal, replace the
photosensitive drum.
Check the following, and replace them if
necessary:
1. Laser (for output)
2. Potential control system
3. Photosensitive drum
Darker image
Default
-10 0 +10 +20 +30 +40 +50
Chapter 13
0008-7911
13-3