Brother MFC-7450

1-57
Confidential
12. OTHERS PROBLEMS
■ The machine is not turned on, or the LCD indication does not appear.
■ The fan does not work.
Step Cause Check Result Remedy
1
Harness
connection
failure of panel
PCB
Is the harness of the
panel PCB ASSY
connected correctly?
No
Reconnect the panel PCB
ASSY harness.
2
Panel PCB
failure
Is the problem solved
after replacing the panel
PCB ASSY?
Ye s
Replace the panel PCB
ASSY.
3
LCD failure Is the problem solved
after replacing the LCD?
Ye s
Replace the LCD.
4
LVPS PCB failure Is the problem solved
after replacing the LVPS
PCB unit?
Ye s
Replace the LVPS PCB
unit.
5
Main PCB failure Is the problem solved
after replacing the main
PCB ASSY?
Ye s
Replace the main PCB
ASSY.
Step Cause Check
Result Remedy
1
Harness
connection
failure of the fan
motor 60 ASSY.
Is the harness of the fan
motor 60 ASSY
connected correctly?
No
Reconnect the harness of
the fan motor 60 ASSY
correctly.
2
Toner LED PCB
ASSY failure
Is the problem solved
after replacing the toner
LED PCB ASSY?
Ye s
Replace the toner LED
PCB ASSY.
3
Main PCB failure Is the problem solved
after replacing the main
PCB ASSY?
Ye s
Replace the main PCB
ASSY.