Poor Fixing - Brother HL-4040CN Service Manual

Dark
User Check
- Check the machine's environment. High temperature and high humidity
conditions can cause this problem.
- Replace the toner cartridge or drum unit with a new one.
- Implement calibration from the control panel.
Step Cause
1 Corona wire
conduction failure
2 Dirt on belt unit
electrode
3 Transfer HVPS
PCB failure
4 Charge HVPS
PCB failure
5 Engine PCB
failure

Poor fixing

User Check
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
- Implement calibration from the control panel.
Step Cause
1 Fuser unit failure
2 Low-voltage
power supply
PCB failure
3 Transfer HVPS
PCB failure
4 Charge HVPS
PCB failure
Check
Are the electrodes on the
drum unit and machine
body dirty?
Are the electrodes on the
belt unit and machine
body dirty?
Is the problem solved
after replacing the
transfer HVPS PCB
ASSY?
Is the problem solved
after replacing the charge
HVPS PCB ASSY?
Is the harness connected
between the HVPS PCB
and engine PCB
correctly?
Check
Is the problem solved
after replacing the fuser
unit?
Is the problem solved
after replacing the PS
PCB unit?
Is the problem solved
after replacing the
transfer HVPS PCB
ASSY?
Is the problem solved
after replacing the charge
HVPS PCB ASSY?
1-44
Remedy
Result
Yes Clean both electrodes.
Yes Clean both electrodes.
Yes Replace the transfer
HVPS PCB ASSY.
Yes Replace the charge
HVPS PCB ASSY.
Yes Replace the engine PCB
ASSY.
Remedy
Result
Yes Replace the fuser unit.
Yes Replace the PS PCB unit.
Yes Replace the transfer
HVPS PCB ASSY.
Yes Replace the charge
HVPS PCB ASSY.
Confidential