The Drum Heater Fails To Operate - Canon CLC 1120 Service Manual

51

The drum heater fails to operate.

Cause
Environment
switch (SW6)
AC fuse PCB
Drum heater (H3)
Thermistor (TH)
Connector, wiring
Drum heater
brush
Drum heater
controller PCB
SSR2 (100/120-V
model only)
DC driver PCB,
CPU PCB
Note: Step 8 applies to the 100/120-V model only.
COPYRIGHT © 1999 CANON INC.
Step
1 Turn off the environment switch. Is
the problem corrected?
2 Is there electrical continuity
between J14-1 and -3 of the AC
fuse PCB?
3 Remove the drum heater, and set
the meter range to x100 , and
connect the meter probes to J22-1
and J22-3 of the heater; does the
index of the meter swing?
4 Set the meter range to x100 , and
connect the meter probes to J22-5
and J22-6. Does the meter index
swing?
5 Are the connection and wiring
between the following connectors
normal?
J9, J5, J21, J22
· environment switch
· SSR2 (100/120-V model only)
· drum heater
6 Disconnect the power plug, and
remove the flywheel. Is the contact
of the drum heater brush normal?
7 Replace the drum heater controller
PCB. Is the problem corrected?
8 Mount the drum heater and the
flywheel, and connect the power
plug. Set the meter range to 12
VDC, and measure the voltage
between J1025-1 (+; DRHOFF)
and J1025-3 (-; GND) of the DC
driver PCB. Is it about 0 V?
CANON CLC1120/1130/1150 REV.0 MAR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 13 TROUBLESHOOTING
Checks Yes/No Action
YES End. (The heater will
remain powered at all
times).
NO Find out the cause, and
replace the AC fuse
PCB.
NO Replace the drum heater.
NO Replace the drum heater.
NO Connect the connectors
properly.
NO Mount the brush
properly. Or, replace the
brush.
YES End.
YES Replace SSR2.
NO Replace the DC driver
PCB or the CPU PCB.
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