Canon iR105 Service Manual page 380

CHAPTER 6 TROUBLESHOOTING
c. Zero-Level Check
One way of finding out if the surface potential control circuit is good or not is to use a
zero-level check.
A zero-level check is made to see if the microprocessor registers 0 V when
the surface potential of the drum is 0 V.
REF.
Using the result of the check, you can find out if the microprocessor on the DC controller
PCB or the measurement unit is good or not; a zero-level check may take either of the fol-
lowing two methods:
1. Method 1
1) Turn off the power switch.
2) Short the connectors J522-1 and -2 on the DC controller PCB with a jumper wire, and
disconnect the connector J3 of the potential control PCB.
6-48
J522
F06-207-06
COPYRIGHT© 2001 CANON INC.
Connector (J3)
2000 2000 2000 2000 CANON iR105 REV.0 JULY 2001