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17. E202 (The keys on the control panel are locked.)
18. E203
19. E204 (The keys on the control panel are locked.)
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
11-95
Cause
Scanner
original leading
edge sensor
1/2 (PS3/4)
DC controller
PCB
Checks
Does the scanner move forward
when the Copy Start key is
pressed?
Is the scanner original leading
edge sensor 1/2 (PS3/4) normal?
(See the instructions on how to
check the photointerrupters.)
Step
1
2
YES/NO
NO
NO
YES
Action
See “The scanner fails
to move forward.”
Check the wiring from
the DC controller PCB to
PS3/4; if normal, replace
PS3/4.
Replace the DC
controller PCB.
Cause
Scanner home
position sensor
DC controller
PCB
Checks
Is the scanner at home position
when ‘E202’ is indicated?
Is the scanner home position
sensor (PS1) normal?
Step
1
2
YES/NO
NO
NO
YES
Action
See “The scanner fails
to move forward.”
Replace the scanner
home position sensor.
Replace the DC
controller PCB.
Cause
Scanner home
position sensor
(PS1)
DC controller
PCB
Checks
Is the scanner at home position
when E202 turns on?
Is the scanner home position
sensor (PS1) normal? (See the
instructions on how to check
photointerrupters.)
Step
1
2
YES/NO
NO
YES
NO
Action
See “The scanner fails
to rotate.”
Check the wiring from
the DC controller to PS1;
if normal, replace the
sensor PS1.
Replace the DC
controller PCB.