Vertical Streaks - Brother HL-4040CN, HL-4050CDN, HL-4070CDW Service Manual

Vertical streaks

Step Cause
1 Dirt in the paper
feed system
2 Scratch on the
exposure drum
3 Exposure drum
dirty
4 Scratch on the
heat roller
Note:
If the machine prints the same pattern, especially including vertical streaks, continuously, black
vertical streaks may appear on the paper since the electrostatic performance of the exposure
drum is decreased temporally.
Vertical streaks in a light background
User Check
- Clean the inside of the machine and the corona wire in the drum unit.
- Replace the toner cartridge with a new one.
Step Cause
1 Drum unit failure
User Check
- This problem may occur with noise which is caused by dirt on
the corona wire in the drum unit. In this case, clean the corona
wire with the wire cleaner.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Check
Is the paper tray or feed
system on the drum unit
dirty with toner?
Is there a scratch on the
surface of the exposure
drum?
Is there vertical dirt with
toner on the surface of
the exposure drum?
Is there a scratch on the
surface of the heat roller?
Check
Is the problem solved
after replacing the drum
unit?
1-47
Remedy
Result
Yes Wipe dirt off.
Yes Replace the drum unit.
Yes Replace the drum unit.
Yes Replace the fuser unit
Remedy
Result
Yes Replace the drum unit.
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