Horizontal Lines - Brother HL-3040CN Service Manual

■ Horizontal lines

Step Cause
1 Dirt on charged
electrode
2 Paper tray ground
terminal provided
in machine body
3 Toner attached on
the develop roller
4 Scratch on the heat
roller
5 HVPS control PCB
failure
6 High-voltage power
supply PCB failure
< >
User Check
- The paper tray ground terminal provided in the machine
body may be dirty. Clean the contact with a dry cloth.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
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?
Are the horizontal lines
at 31 mm (develop roller
circumference)
intervals?
Are the horizontal lines
at 78 mm (heat roller
circumference)
intervals?
Is the problem solved
after replacing the HVPS
control PCB ASSY?
Is the problem solved
after replacing the
high-voltage power
supply PCB ASSY.
3-76
Remedy
Result
Yes Clean both electrodes.
(Refer to Fig. 3-3 (P3-32)
and Fig. 3-6 (P3-33))
Yes Correct bending of
paper tray ground
terminal.
Yes This symptom might
disappear after making
approximate 10 prints.
Yes Replace the fuser unit.
Yes Replace the HVPS
control PCB ASSY.
Yes Replace the
high-voltage power
supply PCB ASSY.
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