Canon iR8500 Service Manual page 482

Pre-transfer charging assembly
8) Is the pre-transfer charging assembly securely fitted?
NO:
Potential control, Photosensitive drum, Developing bias control
9) Turn off and then on the power switch. Check the setting of 'VLIM'
NO:
YES: Check the control system of the developing bias.
COPYRIGHT© 2001 CANON INC.
Fit the charging assembly securely.
and 'VDM' in service mode: COPIER>DISPLAY>DPOT. Are they
as follows?
VL1M: from 50 to 90
VDM: from 360 to 420
Check the power supply control system; if normal, replace the pho-
tosensitive drum.
2000 2000 2000 2000
CHAPTER 6 TROUBLESHOOTING
CANON iR8500/7200 REV.1 AUG. 2001
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