Canon NP6251 Service Manual page 647

CHAPTER 11 TROUBLESHOOTING
54. The fixing heater fails to operate.
Cause Step
Thermal switch
(TP1)
Fixing heater
(H1, H2)
AC driver PCB
DC controller
PCB
11-116
COPYRIGHT © 1997 CANON INC.
Checks
1 Slide out the fixing assembly, and
connect the probes of the tester to
both terminals of the thermal
switch (TP1). Is there electrical
continuity?
2 Slide out the fixing assembly, and
connect probes of the meter to
both terminals of the fixing heater
(H1, H2). Is there electrical
continuity?
3 Is the voltage between the
connectors on the DC controller
PCB indicated in the table 5 V?
Heater
Main heater (H1)
Sub heater (H2)
YES/NO
(+) (–)
J102B-5 J102B-1
J102B-3 J102B-1
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
NO Replace the thermal
switch.
NO Replace the fixing
heater.
YES Replace the AC driver
PCB.
NO Replace the DC
controller PCB.