Brother HL-4040CN - Menu Navigation and Settings

Confidential
1-59
7. OTHERS PROBLEMS
The machine is not turned on, or the LCD indication does not appear.
Step Cause Check Result Remedy
1
Harness
connection failure
of LCD panel
PCB
Is the harness of the LCD
panel PCB ASSY
connected correctly?
No Reconnect the LCD
panel PCB ASSY
harness
2
LCD panel PCB
failure
Is the problem solved
after replacing the LCD
panel PCB ASSY?
Yes Replace the LCD panel
PCB ASSY.
3
LCD panel failure Is the problem solved
after replacing the LCD
panel ASSY?
Yes Replace the LCD panel
ASSY.
4
Low-voltage
power supply
failure
Is the problem solved
after replacing the PS
PCB unit?
Yes Replace the PS PCB unit.
5
Main PCB failure Is the problem solved
after replacing the main
PCB ASSY?
Yes Replace the main PCB
ASSY.
The fan does not work.
(Verify the position of each fan referring to “1.4.16 Operational Check of Fans (Function code
78)” in Chapter 5.)
Step Cause
Check Result Remedy
1
Harness
connection failure
of the appropriate
fan
Is the harness of the
appropriate fan connected
correctly?
No Reconnect the harness of
the appropriate fan
correctly.
2
Charge HVPS
PCB failure
Is the problem solved
after replacing the charge
HVPS PCB ASSY?
Yes Replace the charge
HVPS PCB ASSY.
Replace the fuser unit fan
(FU) and air intake fan
(AIR).
3
Low-voltage
power supply
failure
Is the problem solved
after replacing the PS
PCB unit?
Yes Replace the PS PCB unit.
Replace the LVPS fan
(PS).
4
Engine PCB
failure
Is the problem solved
after replacing the engine
PCB ASSY?
Yes Replace the engine PCB
ASSY. Replace the drum
unit fan (OPC).
5
Main PCB failure Is the problem solved
after replacing the main
PCB ASSY?
Yes Replace the main PCB
ASSY.