2-35
Confidential
Error code 7800
After the first side is printed in 2-sided printing mode, the registration front sensor does not
detect paper pass after a set period of time.
<User Check>
• Remove the jammed paper.
• Close the back cover correctly.
Error code 8903
The back cover sensor detected the open state when 2-sided printing is started (before the
registration of printing in the engine).
Error code 8904
The back cover sensor detected the open state during 2-sided printing (after the registration of
printing in the engine).
<User Check>
• Close the back cover correctly.
• Check that the duplex tray is set correctly.
Step
Cause
Remedy
1
Foreign object in the rear of the
machine or duplex tray
Remove the foreign object.
2
Gears in the paper feed system
coming off
Reattach the paper feed gear.
3
Duplex tray failure
Replace the duplex tray.
4
Damaged gears in the paper
feed drive system
Replace the frame L unit.
5
Main PCB failure
Replace the main PCB ASSY.
Step
Cause
Remedy
1
Duplex tray is not set correctly
Reattach the duplex tray correctly.
2
Back cover sensor attachment
failure
Reattach the back cover sensor.
3
Breakage of boss that presses
the back cover sensor
Replace the back cover.
4
Guide which pushes the back
cover sensor of the duplex tray is
faulty
Replace the duplex tray.
5
Back cover sensor failure
Replace the eject sensor PCB ASSY.
6
Main PCB failure
Replace the main PCB ASSY.