2-52
Confidential
All black
Dirt on back side of paper
<User Check>
• Clean the corona wire of the drum unit.
• Replace the drum unit with a new one.
Step
Cause
Remedy
1
Dirt on the electrodes of the
drum unit, toner cartridge and
those of the machine
Clean the electrodes of the drum unit, toner
cartridge and those of the machine. (Refer to
and
2
Laser unit flat cable failure
Replace the laser unit flat cable.
3
Dirt on the electrodes of the
high-voltage power supply
PCB and those of the
machine
Clean the electrodes of the high-voltage
power supply PCB and those of the machine.
4
High-voltage power supply
PCB failure
Replace the high-voltage power supply PCB
ASSY.
5
Laser unit failure
Replace the laser unit.
6
Main PCB failure
Replace the main PCB ASSY.
<User Check>
• This problem may disappear after printing multiple
sheets of paper.
• Replace the drum unit with a new one.
Step
Cause
Remedy
1
Dirt in the paper feed system
Wipe dirt off.
2
Dirt on the fuser unit
Replace the fuser unit.
3
High-voltage power supply
PCB failure
Replace the high-voltage power supply PCB
ASSY.
