Brother DCP-7080 Service Manual page 107

 Black vertical streaks on a light background
Step
Dirt on the charge electrodes
1
Laser unit failure
2
 Horizontal streaks
Step
Dirt on the charge electrodes
1
FG harnesses or FG plate
attachment failure (not grounded
2
correctly)
Scratch or dirt on the fuser unit
3
High-voltage power supply PCB
4
failure
<User Check>
- Clean the corona wire of the drum unit.
- This problem may disappear after printing multiple sheets of paper.
- Refer to the User's Guide to remove the dirt from the exposure drum
using a cotton applicator.
- Turn ON the power switch, and leave the machine for a while
(condensation).
- Replace the drum unit with a new one.
- Replace the toner cartridge with a new one.
Cause
<User Check>
- Clean the corona wire of the drum unit.
- This problem may disappear after printing multiple sheets of paper.
- Refer to the User's Guide to remove the dirt 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
2-72
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
Fig. 2-9.)
Replace the laser unit.
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
Fig. 2-9.)
Retighten the screws to secure the FG
harnesses or FG plate.
Fix the bent tray ground spring of the paper
tray. (Refer to Fig. 2-13.)
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Fig. 2-8 and
Fig. 2-8 and
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