The Print Is Blank - Canon Image Reader-A1 iR5000i Service Manual

CHAPTER 4 TROUBLESHOOTING IMAGE FAULTS/MALFUNCTIONS

3.21 The print is blank

Reader unit
1) Does the problem occur only in copy images?
YES: Check the connection of the following PCBs; if normal, replace the
1.
2.
Primary charging assembly
2) Make the following selections in service mode:
COPIER>DISPLAY>DPOT.
NO:
1.
2.
3.
Developing assembly locking unit
3) During printing, is the developing assembly locked against the photo-
sensitive drum?
NO:
Developing assembly drive assembly
4) During copying, is the developing assembly rotating?
NO:
Transfer charging assembly
5) Is the transfer charging assembly fitted fully and securely?
NO:
6) Is leakage found in the transfer charging assembly?
YES: Check the transfer charging assembly.
NO:
1.
2.
4-18 T
PCB.
CCD/AP PCB
DC controller PCB
(Copier) Are the readings <VDM> ± 6V of the <VDT> ?
(Printer) Are the readings <VDM-P> ± 6V of the <VDT-P> ?
Check the primary charging assembly.
Check the HVT PCB.
Check the potential sensor and the potential control PCB.
Check the mechanism of the developing assembly locking unit.
Check the drive system for the developing assembly.
Fit it securely.
Replace the DC controller PCB.
Replace the main controller PCB.
COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR5000i/iR6000i REV.0 JUNE 2001