2-82
Confidential
■ Faulty registration
■ Dark
User Check
• Check that the appropriate media type is selected in the 
driver.
Step Cause Remedy
1
Adjusted value of the laser unit 
mistake
Refer to 
"2.1 Inputting the Adjusted Value of 
the Laser Unit" in Chapter 4
, and enter the 
adjusted value of the laser unit again.
2
Registration rear actuator catching 
on some position
Correct catching of the registration rear 
actuator.
User Check
• Check the machine's environment. High temperature and high 
humidity or low temperature and low humidity conditions can cause 
this problem.
• Adjust the density by the Density Adjustment.
• Clean the corona wire of drum unit.
• Replace the drum unit with a new one.
• Replace the toner cartridge with a new one. If remove the used 
toner cartridge and replace a relatively new used toner cartridge, 
this case is caused.
Step Cause Remedy
1
Dirt on the electrodes of the drum 
unit and the machine body
Clean the electrodes of the drum unit and 
machine body. (Refer to Fig. 2-11, Fig. 2-
12.)
2
High voltage power supply PCB 
ASSY failure
Replace the high voltage power supply 
PCB ASSY.
3 Laser unit failure Replace the laser unit.
4 Main PCB failure Replace the main PCB ASSY.