COPYRIGHT © 2000 CANON INC. 2000 2000 2000 2000 CANON iR5000/iR6000 REV.0 JULY 20002-2 TCHAPTER 2 IMAGE ADJUSTMENT BASIC PROCEDURE2. Making Checks on the Printer Unit (1/2)Is there adifference in density betweenfront and rear?Is the rear lighter?Turn the adjusting screwfound at the front of theprimary charging assemblyclockwise. (2 full turns max.)Turn the adjusting screwfound at the rear of theprimary charging assemblyclockwise. (2 full turns max.)Generate one print of a halftone image.Is it foggy?Are the readings ± 6 Vof the target value?(*1)Are the readings 70 ± 15 V? YESNOYESNOYESNONOYESNOYESYESNOAre there verticallines in the image?Are there verticallines in the image?Checking Halftone ImagesYESYESNONOExecute forcedpotential control.Generate a halftone image. Generate a blank print.Make the selections in service mode, and turn offand then on the main power switch:COPIER>FUNCTION>DPC>DPC.Check the following readings in service mode:COPIER>DISPLAY>DPOT>VL1M (for copier image)COPIER>DISPLAY>DPOT>VL1M-P (for printer image)Check the following readings in service mode:COPIER>DISPLAY>DPOT>VL2M (for copier image)COPIER>DISPLAY>DPOT>VL2M-P (for printer image)Check the following readings in service mode:COPIER>DISPLAY>DPOT>VDM (for copier image)COPIER>DISPLAY>DPOT>VDM-P (for printer image)ACheck the following, and replace them ifnecessary:1. Laser (for output)2. Potential control system3. Photosensitive drumCheck the following, and replace them ifnecessary.1. Laser (for output)2. Potential control system3. Photosensitive drumCheck the primary chargingsystem and the potential controlsystem; if normal, replace thephotosensitive drum.Clean the following; also checkfor foreign matter:1. Dust-proofing glass2. Charging assemblies1. If there still is a difference in density after giving the adjusting screw 2 turns (each turncausing a change of about 0.7 mm), check the scanning lamp and the scanner for soiling.2. When making a clockwise turn, be sure that the intervals between wire grid runs are notlarger than 9 mm.When making a counterclockwise turn, be sure that the intervals between wire grid runsare not smaller than 7.5 mm.3. The machine will not execute potential control even when the main power switch isturned off and then on if the temperature of the fixing assembly is 150˚C or higher.-50 -40 -30 -20 -10 0 +10 +20 +30 +40 +50DefaultLighter image Darker imageAdjusting 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)Adjust the offset value of the VL target potential.MemoAre the readings ± 6 Vof the target value?(*2)REF.*1:VD target valueCOPIER >DISPLAY >DPOT >VDT (for copier image)COPIER >DISPLAY >DPOT >VDT-P (for printer image)*2:VL1 target valueCOPIER >DISPLAY >DPOT >VD1T (for copier image)COPIER >DISPLAY >DPOT >VD1T-P (for printer image)Moving the wire from the photosensitive drum causes the image to be lighter, whilemoving it closer causes the images to be darker.Download Free Service Manual at http://printer1.blogspot.com
