2-109
Confidential
■ Unstable color density
■ Hollow print
<User Check>
• Make a print on a different type of paper.
• Replace the belt unit with a new one.
• Replace the waste toner box with a new one.
• Replace the toner cartridge with a new one.
• Replace the drum unit with a new one.
Step Cause Remedy
1
Dirt on the electrodes of the 
drum unit and those of the 
machine
Clean the electrodes of the drum unit and 
those of the machine. (Refer to Fig. 2-6 (P2-
63) and Fig. 2-7 (P2-63).)
2
Dirt on the electrodes of the 
belt unit and those of the 
machine
Clean the electrodes of the belt unit and 
those of the machine. (Refer to Fig. 2-6 (P2-
63) and Fig. 2-11 (P2-94).)
3
High-voltage power supply 
PCB failure
Replace the high-voltage power supply PCB.
4 LED ASSY failure Replace the appropriate LED ASSY.
5 Main PCB failure Replace the main PCB.
<User Check>
• Check the usage environment of the machine. Using the machine in 
hot-humid or cold-dry conditions can cause this problem.
• Refer to <How to clean the drum unit> to remove the dirt from the 
exposure drum using a cotton applicator.
• Replace the toner cartridge with a new one.
• Replace the drum unit with a new one.
Step Cause Remedy
1
Dirt on the paper dust 
cleaning roller of the T1
Refer to the Fig. 2-8 (P2-83) to clean the 
paper dust cleaning roller.
2
Scratch or dirt on the fuser 
unit
Replace the fuser unit.
3
High-voltage power supply 
PCB failure
Replace the high-voltage power supply PCB.