Brother MFC-7450

1-31
Confidential
<Location of the laser beam window>
Fig. 1-6
■ Faulty registration
■ Dark
User Check
• Check that the appropriate media type is selected in the
printer driver.
Step Cause Check
Result Remedy
1
Registration rear
actuator catching
in some position
Does the registration
rear actuator move
smoothly?
No
Re-assemble the
registration rear actuator
and ensure smooth
operation.
User Check
• Check the machine's environment. High temperature and high
humidity conditions can cause this problem.
• Replace the drum unit with a new one.
• Replace the toner cartridge with a new one.
Step Cause Check
Result Remedy
1
The developing
bias voltage
failure
Is the problem solved
after resetting the
developing bias
counter?
Ye s
Reset the developing bias
counter. (Refer to "2.2
Resetting the developing
bias voltage counter" in
Chapter 5)
2
HVPS PCB
failure
Is the problem solved
after replacing the
HVPS PCB ASSY?
Ye s
Replace the HVPS PCB
ASSY.
3
Main PCB failure Is the problem solved
after replacing the main
PCB ASSY?
Ye s
Replace the main PCB
ASSY.