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37. The vertical path roller fails to rotate.
38. The registration roller fails to rotate.
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
11-107
Cause
Belt, Gear,
Coupling
Registration
paper sensor
(PS23)
Registration
roller drive
clutch (CL9)
DC controller
PCB
Checks
Is the drive from the main motor
(M1) transmitted to the registration
roller through the belt, gear, and
coupling?
Is the registration paper sensor
(PS23) normal?
Connect the – probe of the meter
to GND and the + probe to J108A-
5. Does the voltage change from
about 24 to 0 V as soon as the
registration roller starts to rotate?
Step
1
2
3
YES/NO
NO
NO
YES
NO
Action
Install the belt, gear, and
coupling correctly.
Replace the sensor
(PS23).
Replace the clutch
(CL9).
Replace the DC
controller PCB.
Cause
Belt, Gear,
Coupling
Vertical path
roller clutch
DC controller
PCB
Checks
Is the drive from the pick-up motor
(M2) transmitted to each vertical
path roller through the belt, gear,
and coupling?
Connect the – probe of the tester
to GND and the + probe to the ter-
minal indicated. Does the voltage
change from about 24 to 0 V as
soon as the roller starts to rotate?
Vertical path 0 drive clutch (CL18)
J115A-4
Vertical path 1 drive clutch (CL15)
J117A-15
Vertical path 2 drive clutch (CL17)
J121B-8
Vertical path 3 drive clutch (CL11)
J117B-2
Vertical path 4 drive clutch (CL13)
J130B-2
Step
1
2
YES/NO
NO
YES
NO
Action
Install the belt, gear, and
coupling correctly.
Replace the appropriate
clutch.
Replace the DC
controller PCB.