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Service Bulletin COPIER
Issued by Canon Europa N.V.
Model : GP405/335 No.: GP405-010
(FF-T01-J7-000028-01)
DATE: 10.09.99
Location : SERVICE MANUAL (FY8-13FV-000)
Subject : UPDATING IMAGE BASIC ADJUSTMENT PROCEDURE
Reason : The descriptions for the "Image Basic Adjustment Procedure" found on p. 14-3 of the
Service Manual (FY8-13FV-000) are not adequate, requiring modification.
Reference:
In the case of a digital copier, the following mechanisms are employed to enhance the reproduction of
images:
1. edge emphasis processing
2. density processing
As a result, the overall density of images tends to appear higher (darker) when compared with the
density of images produced by an analog copier.
Details : For specific changes, see the pages that follow.
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GP405-010
1 Making Initial Checks
Conditions for Making Image Adjustments Output Condition Using the NA3 Test Chart, make 2 copies in the following
Execute `roller cleaning', which is under
1. Be sure to use copy paper fresh out of package. `ADJUSTMENT/CLEANING' of user mode. F value = 5 mode:
(Moist paper will make evaluation of image quality 1. text mode
Reference:
difficult.) Reference: At the optimum density, the copy should barely
Execute cleaning for the following:
2. Be sure to use copy paper with a high degree of show gray scale No. 10.
1. Primary charging roller
whiteness.
2. Transfer charging roller
3. If possible, be sure to use A3 paper.
Generate 2 each of the following test prints:
COPIER>TEST>PG
1. TYPE 4 (solid white)
Clean the separation static eliminator.
2. TYPE 5 (halftone)
3. TYPE 6 (solid black)
Is the setting
of `density correction', which No Set it to the
If only the copy images have a fault,
is under `ADJUSTMENT/CLEANING' middle.
of user mode, at the
middle?
Go to
Yes 2 Checking the Scanner Side (1/2)
Is the setting of
ADJUST>DENS>DENS-ADJ No Set it to `5'.
of service mode `5'?
Yes
If the test print images have faults,
Items under COPIER>ADJUST of service mode Enter the
Are the seven Go to
1. AE>AE-TBL settings
items on the left in service No
2. DEVELOP>DE-DC indicated on
mode identical to those 4 Checking the Printer Side (1/3)
3. DEVELOP>DE-NO-D indicated on the service the service
4. DEVELOP>DE-OFST label? label.
5. HV-PRI>P-DC
6. HV-PRI>P-NO-DC
7. HV-PRI>OFST1-DC Yes
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GP405-010
2 Checking the Scanner Side (1/2)
Check/clean the following; if the scanning lamp
has reached the end of its life, replace it:
1. mirrors 2. lens
3. standard white plate 4. copyboard glass
5. dust-proofing glass 6. scanning lamp
7. reflecting plate
Make a copy in text mode.
Are there Is the white Is the Yes
No No Make a copy in AE mode.
vertical lines in the background of the copy density of the copy image
image? foggy? normal?
Yes Yes No
Execute the following in service mode: Execute the following in service mode: Change the setting of the following in Is the Yes
COPIER>FUNCTION>CCD>CCD-ADJ. COPIER>FUNCTION>CCD>CCD-ADJ. service mode: density of the copy image
For detailed instructions, see the Service Manual. COPIER>ADJUST>DENS>DENS-ADJ. normal?
If the density is too high (dark), decrease
No
the setting.
Are there If the density is too low (light), increase Change the setting of the following
No No the setting.
vertical lines in the Is the image foggy? in service mode:
image? COPIER>ADJUST>AE>AE-TBL.
If the density is too high (dark),
Yes Yes decrease the setting.
Go to Is the If the density is too low (light),
Execute the following in service mode: Yes
density of the copy image increase the setting.
COPIER>FUNCTION>CCD>MAN-ADJ.
For detailed instructions, see the Service Manual.
6 Checking the Printer Side (3/3) normal?
No
Are there No
vertical lines in the
image? A End.
Yes
Go to
4 Checking the Printer Side (1/3)
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GP405-010
3 Checking the Scanner Side (2/2)
Reference:
Changing the setting of DENS-ADJ will
change the density in all the following modes: