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Confidential
 Error code 6901
An error occurred in the fuser unit when the power switch was turned ON or sleep mode was 
released.
Error code 6902
Rechecking the error after the power switch was turned OFF and then ON again because an 
error was detected in the fuser unit.
(This message is displayed for approximately 15 minutes when the machine is restarted after 
error code 6901 has occurred.)
Self-Diagnostic
Turn the power off, then on again. Leave the machine for 15 min.
Self-Diagnostic
Will Automatically Restart within 15 minutes.
Step Cause Remedy
1
Connection failure of each fuser 
unit harness
Reconnect each harness of the fuser unit.
2
Connection failure of the eject 
sensor PCB flat cable
Reconnect the eject sensor PCB flat cable.
3
Fuser unit failure Replace the fuser unit.
4
Eject sensor PCB failure Replace the eject sensor PCB ASSY.
5
Low-voltage power supply PCB 
failure
Replace the low-voltage power supply PCB 
ASSY.
6
Main PCB failure Replace the main PCB ASSY.
Note:
• Turn OFF the power switch. After the fuser unit has cooled sufficiently, turn ON the 
power switch again and leave the machine for 15 minutes. This problem may then be 
cleared.
• To release the fuser unit error after taking appropriate measures, enter the 
maintenance mode once and quit it with the maintenance code 99.