Brother HL-5440D Service Manual page 103

White horizontal streaks
<User Check>
- This problem may disappear after printing multiple sheets of paper.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Step
Dirt on electrodes of the drum unit
1 and those of the machine
Dirt on electrodes of the toner
2 cartridge and those of the machine
3 Fuser unit failure
High-voltage power supply PCB
4
failure
When the machine has not been used for long periods, try printing
several sheets of paper.
Cause
2-67
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
Fig. 2-7.)
Clean the electrodes of the toner cartridge
and those of the machine. (Refer to
Fig. 2-7.)
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Fig. 2-6 or
Fig. 2-6,
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