Brother HL-L2300D Service Manual page 83

 Single-colored dot or dirt
Step
Accumulated paper dust
1
Clogged filter
2
Scratch or dirt on the fuser unit
3
High-voltage power supply PCB
4
failure
Note:
• Image defects which appear periodically may be caused by failure of rollers. Refer to
the table below and determine the cause based on the diameter of the rollers or the
pitch at which defects appear on the image.
<Pitch appears in the image and rollers >
Part name
Develop roller
Exposure drum
Heat roller in the fuser unit
Pressure roller in the fuser unit
 Black band
Step
FG harnesses or FG plate
attachment failure (not grounded
1
correctly)
Laser unit failure
2
<User Check>
- Check that the paper is not damp.
- 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
32.4 mm
94.2 mm
78.5 mm
78.5 mm
<User Check>
- Clean the corona wire of the drum unit.
- Return the corona wire cleaning tab to the "▲" position.
- 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
2-65
Remedy
Remove the paper dust cleaning roller cover
and get rid of the paper dust in the area
described in Fig. 2-7.
Clean the filter.
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
Pitch at which defects
appear in the image
Remedy
Retighten the screws to secure the FG
harnesses or FG plate.
Fix the bent tray ground spring of the paper
tray. (Refer to Fig. 2-10.)
Replace the laser unit.
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