Brother DCP-L5500D Service Manual page 136

 Black vertical streaks on a light background
Step
Dirty charge electrodes
1
2 Laser unit failure
 Horizontal streaks
Step
Dirty charge electrodes
1
FG harnesses or FG plate
attachment failure (not grounded
2
correctly)
3 Scratch or dirt on the fuser unit
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 < How to clean the drum unit>
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 < How to clean the drum unit>
exposure drum using a cotton applicator.
• Replace the drum unit with a new one.
• Replace the toner cartridge with a new one.
Cause
2-101
to remove the dirt from the
Remedy
Clean the electrodes of the drum unit and those
of the machine. (Refer to
Replace the laser unit.
to remove the dirt from the
Remedy
Clean the electrodes of the drum unit and those
of the machine. (Refer to
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. 2-9.)
Fig. 2-8 and Fig. 2-9.)
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