Canon iR8500 Servise Manual page 350

Pre-transfer charging assembly
8) Is the pre-transfer charging assembly securely fitted?
NO:
Potential control, Photosensitive drum, Developing bias control
9) Turn offf and then on the power switch. Check the setting of
NO:
YES: Check the control system of the developing bias.
COPYRIGHT© 2001 CANON INC.
Fit the charging assembly securely.
'VLIM' 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 REV.0 MAR. 2001
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