Horizontal Stripes - Brother HL-4040CN Service Manual

Horizontal stripes

User Check
- Clean the inside of the machine and the corona wire in the drum unit.
- Replace the drum unit with a new one.
Step Cause
1 Dirt on the
charged electrode
2 Paper tray ground
terminal provided
in the machine
body
3 Toner attached
on the develop
roller
4 Scratch on the
exposure drum
5 Scratch on the
heat roller
6 Transfer HVPS
PCB failure
7 Charge HVPS
PCB failure
Paper tray ground terminal
Check
Are the electrodes on the
drum unit and machine
body dirty?
Is the paper tray ground
terminal bent, which is
provided in the machine
body? (Refer to Fig. 1-5.)
Are the horizontal stripes
at 37.4 mm (develop roller
diameter) intervals?
Are the horizontal stripes
at 75.0 mm (exposure
drum diameter) intervals?
Are the horizontal stripes
at 78.5mm (heat roller
diameter) intervals?
Is the problem solved
after replacing the
transfer HVPS PCB
ASSY?
Is the problem solved
after replacing the charge
HVPS PCB ASSY?
Fig. 1-5
1-48
Remedy
Result
Yes Clean both electrodes
Yes Correct bending of paper
tray ground terminal.
Yes This problem will
disappear by printing
approximate 10 pages. If
the same problem
occurs, replace the toner
cartridge.
Yes Replace the drum unit.
Yes Replace the fuser unit.
Yes Replace the transfer
HVPS PCB ASSY.
Yes Replace the charge
HVPS PCB ASSY.
Confidential