Brother HL-L5000D Service Manual page 131

 White horizontal streaks
Step
Dirty charge electrodes
1
2 Scratch or dirt on the fuser unit
High-voltage power supply PCB
3
failure
 Faint print
Step
1 Laser unit failure
2 Fuser unit failure
3 Main PCB failure
<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.
Cause
<User Check>
- Check that the machine is positioned on a level surface.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Cause
2-105
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
Fig. 2-7.)
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Remedy
Replace the laser unit.
Replace the fuser unit.
Replace the main PCB ASSY.
Fig. 2-6 and
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