Brother HL-L5000D Service Manual page 135

 Downward fogging of solid color
Step
High-voltage power supply PCB
1
failure
2 Main PCB failure
 Horizontal lines
Step
Dirty charge electrodes
1
2 Scratch or dirt on the fuser unit
High-voltage power supply PCB
3
failure
 Ghost
Step
1 Scratch or dirt on the fuser unit
High-voltage power supply PCB
2
failure
<User Check>
- Replace the toner cartridge with a new one.
Cause
<User Check>
- This problem may disappear after printing multiple
sheets of paper.
- Refer to <How to clean the drum unit>
from the exposure drum using a cotton applicator.
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Cause
<User Check>
- Check the usage environment of the machine. Using the machine in
hot-humid or cold-dry conditions can cause this problem.
- Check that the appropriate paper type is selected in the driver.
- Select "Improve Toner Fixing" in the driver.
- Replace the drum unit with a new one.
Cause
2-109
Remedy
Replace the high-voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
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 fuser unit.
Replace the high-voltage power supply PCB
ASSY.
to remove the dirt
Fig. 2-6 and
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