Canon 1130 Service Manual page 652

10 The copy has a white spot (middle of trailing edge).
A white spot in the middle of the trailing edge of a copy usually takes the following form:
• Principles behind the Fault
This type of fault mostly occurs when
its trailing edge will lose contact with the drum in an increased degree.
This fault tends to occur when copying on the second side of a double-sided copy or in a high
humidity environment.
Cause
------------
------------
Service mode
ADJUST>MISC>
ATT-RTN
(attraction
additional rotation
mode)
ADJUST>HV-
ATT>HV-ATT in
service mode
(attraction high-
voltage output
adjustment mode)
COPYRIGHT © 2002 CANON INC.
Paper
Step
1 Is the problem noted particularly
on thick paper?
2 Is the paper inside the cassette
wavy because of humidity?
3 Is the problem noted in single-
sided copying mode only or when
copying on the first side of a
double-sided copy?
4 Is the problem noted on the second
side of a double-sided copy only?
5 Does the problem occur in single-
sided copying or on the first and
second sides of a double-sided
copy?
6 Decrease the setting of
ADJUST>HV-ATT>ATT-N1 or
ATT-N2 in service mode. Is the
problem corrected?
ATT-N1: for plain paper, single-
sided copying or for
copying on the 1st side
of a double-sided copy
ATT-N2: for copying on the 2nd
side of a double-sided
copy
CANON CLC1100/1130/1150/1160/1180 REV.1 FEB. 2002 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 13 TROUBLESHOOTING
paper is wavy. If its leading edge is not attracted evenly,
Checks Yes/No Action
YES Go to step 7.
YES Replace the paper.
YES Set
ADJUST>MISC>ATT-
RTN3 in service mode
to '1'.
YES Set
ADJUST>MISC>ATT-
RTN4 in service mode
to '1'.
YES Set
ADJUST>MISC>ATT-
RTN3 and ATT-RTN4
in service mode to '1'.
YES End.
Settings: -5 to +5
Unit: 2 µA
White spot
13-81