Making Checks On The Printer Side (1/2) - Canon iR105 Service Manual

CHAPTER 6 TROUBLESHOOTING
1.1.2

Making Checks on the Printer Side (1/2)

<Checking the Images>
n
Use PG4, PG7, and PG8.
Does the
image have a vertical
line?
YES
Clean the following and look for
adhesion of foreign matter:
1. Dust-proofing glass
2. Charging assembly
3. Developing cylinder
Does the
image have a vertical
line?
YES
6-4
<Checking the Density Slope>
NO
Check the image using PG4.
Is there
difference in density
between front and
YES
Is it lighter at the rear?
NO
YES
Turn the adjusting
screw at the front of
the primary charging
assembly
counterclockwise.
(2 turns max.)
Execute potential
control.
Turn off and then on the power
switch, and generate PG7 or PG4
(test print).
Caution:
1. If the difference in density still exists after giving the adjusting
screw 2 turns (one side; a full turn causes a change of about
0.7 mm), check the charging assembly, scanning lamp, and
scanner for dirt.
2. When giving it a counterclockwise turn, be sure that the
distance between wire and grid will not be 7.5 mm or less.
Reference:
Moving the wire from the photosensitive drum causes the images
to be darker; while moving it closer causes the images to be
lighter.
NO
rear?
NO
Turn the adjusting
screw at the rear of the
primary charging
assembly
counterclockwise.
(2 turns max.)
F06-101-02
<Checking the Solid Black Density>
Check PG8 (solid black).
Is the output
YES
free of fuzziness and the
density correct?
NO
Make the following selections in service
mode:
COPIER>DISPLAY>DPOT>VDM.
Check the primary charging
Is the reading of
NO
system and the potential control
<VDM> between 390
system; if normal, replace the
and 460?
photosensitive drum.
YES
Make the following selections in service
mode:
COPIER>DISPLAY>DPOT>VL1M.
Check the following; if
faulty, replace it:
NO
Is the reading of
1. Laser output
<VL1M> between 50
and 90? 2. Potential control system
YES
Check the following of the
Is the test print of YES developing system:
PG6 (blank) foggy?
1. Developing bias
2. Toner coating on sleeve
NO
Execute service mode as follows:
1. Vary the values of the following as indicated in the table:
ADJUST>V-CONT>VD-OFST, ADJUST>V-CONT>VL-OFST:
Lighter images Darker images
Default
VD-OFST -4 -3 -2 0 +2
VL-OFST +4 +3 +2 0 -2
COPYRIGHT© 2001 CANON INC. 2000 2000 2000 2000
A
+3 +4
-3 -4
CANON iR105 REV.0 JULY 2001