Canon CLC 1120 Service Manual page 671

CHAPTER 13 TROUBLESHOOTING
49 The pre-exposure lamp fails to turn off.
Cause
Pre-exposure
lamp (LA1)
Pre-exposure
lamp (LA1)
DC driver PCB,
CPU PCB
13-144
COPYRIGHT © 1999 CANON INC.
Step Checks
1 Turn off the power switch, and
disconnect J1008 of the DC driver
PCB. Set the meter range to x100
, and measure the resistance
between J1008-A1 and -A2 on the
harness side. Is it about 20 ?
2 Connect J1008, and turn on the
power switch. Set the meter range
to 30 VDC, and measure the
voltage between J1008-A1 (+;
24V) and J1008-A2 (-;
PELA1ON). Does it change from
about 0 to about 24 V when the
main motor starts to rotate?
Yes/No
NO
YES
NO
CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
Check the wiring from
J1008 to the pre-
exposure lamp; if
normal, replace the pre-
exposure lamp.
Replace the pre-
exposure lamp.
Replace the DC driver
PCB or the CPU PCB.