Vertical Streaks - Brother HL-3040CN Service Manual

■ Vertical streaks

Note:
You can check this image defect with the function code 71.
(Refer to "1.4.14 Color test pattern (Function code 71)" in Chapter
Step Cause
1 Dirt in the paper
feed system
2 Exposure drum
dirty
3 Bend of tray ground
spring
4 Scratch on the heat
roller
5 LED ASSY failure
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.
Tray ground spring
< >
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.
- 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 vertical dirt with
toner on the surface of
the exposure drum?
Is the tray ground spring
bent?
(Refer to Fig. 3-10)
Is there a scratch on the
surface of the heat roller?
Is the problem solved
after replacing the LED
ASSY?
Paper tray
Fig. 3-10
3-65
7.)
Remedy
Result
Yes Wipe dirt off.
Yes Clean the drum unit.
Yes Replace the paper tray.
Yes Replace the fuser unit.
Yes Replace the LED ASSY.
<Bottom of paper tray>
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