E121-0002; E202 (The Keys In The Control Panel Become Locked); E204 (The Keys In The Control Panel Become Locked) - Canon iR8500 Service Manual

4.1.26 E121-0002

Foreign matter
1) Is there foreign matter that prevents the rotation of the fan around
YES: Remove the foreign matter.
Connector
2) Is the connector J503 on the DC controller PCB connected se-
NO:
Laser driver cooling fan (FM5), DC controller PCB
3) Try replacing the laser driver cooling fan (FM5). Is the problem
YES: End.
NO:

4.1.27 E202 (The keys in the control panel become locked)

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1) When 'E202' is indicated, is the scanner in home position?
NO:
Connector
2) Is the connector J1702 of the relay PCB connected properly?
NO:
Scanner home position sensor (PS1), Reader controller PCB
3) Is the scanner home position sensor (PS1) normal? (See 2.10
YES: Check the wiring from the reader controller PCB to PS1; if normal,
NO:

4.1.28 E204 (The keys in the control panel become locked)

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1) Does the scanner move forward when the Start key is pressed?
NO:
Image leading edge sensor (PS3), Reader controller PCB
2) (See 2.10 "Checking the Photointerrupters.")
NO:
YES: Replace the Reader controller PCB.
COPYRIGHT© 2001 CANON INC.
the laser drive cooling fan?
curely?
Connect it securely.
corrected?
Replace the DC controller PCB.
See 4.1.86 "The scanner fails to move forward."
Connect the connector properly.
"Checking the Photointerrupters.")
replace PS1.
Replace the reader controller PCB.
See 4.1.86 "The scanner fails to move forward."
Check the wiring form the Reader controller PCB to PS3; if nor-
mal, replace PS3.
2000 2000 2000 2000
CHAPTER 6 TROUBLESHOOTING
CANON iR8500/7200 REV.1 AUG. 2001
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