Canon GP335 Service Manual page 494

CHAPTER 14 TROUBLESHOOTING
16 E202 (The scanner home position is not detected.)
While this code is on, the keys on the control panel are locked and the Wait message is
indicated.
This code is indicated only on the Error History screen in service mode.
Cause
Scanner home
position sensor
(PS1)
DC controller
PCB
Wiring
Scanner motor
(M3)
DC controller
PCB
14-76
Step Check
1 Is the scanner at the home position?
2 Is 5 VDC present at J112-B5 on the
DC controller PCB when the
scanner is at PS1?
3 Clean the sensor light-receiving
section. Is the problem corrected?
4 Is the voltage at J113-A19 about 0
V when PS1S generates 5 VDC?
5 Is there a fault in the wiring from
J116 of the DC controller PCB to
the scanner motor?
6 Replace the scanner motor. Is the
problem corrected?
COPYRIGHT © 1999 CANON INC. CANON 405/335 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Yes/No Action
NO See "The scanner fails to
move forward/in
reverse."
NO Check the wiring from
DC controller PCB
(J112-B5) to PS1; if
normal, replace PS1.
NO Check the wiring from
DC controller PCB
(J112-B5) to PS1; if
normal, replace PS1.
NO Check to make sure that
the J113 connector is
firmly connected; then,
replace the DC
controller PCB.
YES Correct the connection.
YES Check the harness for
continuity; if normal,
replace the scanner
motor.
NO Replace the DC
controller PCB.