Making Checks On The Reader Unit (Ir7200) - Canon iR8500 Service Manual

1.1.5 Making Checks on the Reader Unit (iR7200)

<Making Image Initial Checks>
Are there
NO
vertical lines in the
images?
YES
Clean the following:
1. Mirrors
2. Lens
3. Standard white plate
(mounted to back of
copyboard glass)
4. Copyboard glass
Execute shading in service mode:
COPIER>FUNCTION>CCD>CCD-ADJ
<Checking Halftone Density>
B
When
the A3 Chart
is copied in text/photo
mode, is the density of No.8 optimum
when compared with No.7
through 9?
NO
If it is too light,
Increase the setting of the
following in service mode:
COPIER>ADJUST>DENS>
DENS-ADJ
Make one copy of the A3 Chart in
text/photo mode.
Is the
density of gray scale
No.8 (halftone)
YES
different?
NO
Go to "Checking the Halftone Density" for the printer side.
COPYRIGHT© 2001 CANON INC. 2000 2000 2000 2000 CANON iR8500/7200 REV.1 AUG. 2001
<Checking the Solid Black Density>
<Checking the Density Slope>
Is there
NO
a difference in density
in text mode. Is gray scale No. 1
between front and
rear?
YES
Clean the mirrors.
Execute shading in service mode:
COPIER>FUNCTION>CCD>CCD-ADJ
Is there
NO
adifference in density
between front and
rear?
YES
Perform the instructions under
"Checking the Density Slope"
Executing Potential Control
for the printer unit.
Turn off and then on the power switch;
then, make a copy.
YES
Execute shading adjustment in
End.
service mode:
COPIER>FUNCTION>CCD>CCD-ADJ.
If it is too dark,
Decrease the setting of the
following in service mode:
COPIER>ADJUST>DENS>
DENS-ADJ
Perform the instructions under
"Checking the Solid Black Density"
F06-101-05
<Checking for Fogging>
Make
Make a copy of
a copy of the NA3 Chart
NO
the NA3 Chart in text mode.
Is the white background
(solid black) too light?
YES
Check the life of the
scanning lamp; if it has
reached the end of its
life, replace it.
Clean the following:
1. Mirrors
2. Lens
3. Standard white plate
4. Scanning lamp
5. Reflecting plate
Make a copy of the
NA3 Chart in AE mode. Is the
Is the
NO
density of gray scale
No. 1 (solid black) too
low (light)?
YES
for the printer unit.
CHAPTER 6 TROUBLESHOOTING
Execute shading adjustment in service
YES
mode:
COPIER>FUNCTION>CCD>CCD-ADJ.
foggy?
NO
Perform the instructions
Is the
NO
under "Checking for
white background
Fogging" on the printer side.
foggy?
YES
Increase the white level target value for
shading correction in service mode:
COPIER>ADJUST>CCD>SH-TRGT
(Limit the increase to 40.)
Execute shading adjustment in service
YES
mode:
COPIER>FUNCTION>CCD>CCD-ADJ.
output foggy?
NO
Is the white
NO
background
foggy?
B
YES
Decrease the value of AE density
adjustment in service mode:
COPIER>ADJUST>AE>AE-TBL.
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