Brother HL-4040CN, Service Manual

Page: 72 / 341

Confidential
1-55
Color misregistration
User Check
- Implement the auto color registration by the panel operation.
- Replace the belt unit with a new one.
- Replace the drum unit with a new one.
- Replace the waste toner box with a new one.
Step Cause Check
Result
Remedy
1 Phase shift of
gear 39/121 Check if gear 39/121
phase is shifted? Yes Phase the Gear 39/121.
For the method how to
phase the gear 39/121,
refer to
“Chapter 3
DISASSEMBLY AND
ASSEMBLY”
.
2 Engine PCB
failure Is the problem solved
after replacing the engine
PCB ASSY? Yes Replace the engine PCB
ASSY.
Fogging
User Check
- Replace the toner cartridge with a new one.
- Replace the drum unit with a new one.
- Do not use acid paper.
- Check if there is dust or paper powder in the machine.
Step Cause Check
Result
Remedy
1
Toner sensor
failure (Machine
body) Is the toner sensor
performed normally by
following the procedure
described in
“Maintenance mode 32”
to check.
No Replace the toner sensor
PCB (TE/NEW) of the
appropriate color.
2 Transfer HVPS
PCB failure Is the problem solved
after replacing the
transfer HVPS PCB
ASSY? Yes Replace the Transfer
HVPS PCB ASSY.
3 Charge HVPS
PCB failure Is the problem solved
after replacing the charge
HVPS PCB ASSY? Yes Replace the charge
HVPS PCB ASSY.
4
Engine PCB
failure
Is the problem solved
after replacing the engine
PCB ASSY?
Yes Replace the engine PCB
ASSY.
Note:
This problem often occurs when the drum unit or toner cartridge is nearly at the end of life.