Brother DCP-7090 Service Manual page 133

 Spots or dirt
<User Check>
Step
Dirt on the paper dust
1 cleaning roller of the paper
tray
Dirt on the exposure drum
2
3 Clogged filter
Scratch or dirt on the fuser
4
unit
High-voltage power supply
5
PCB failure
Note:
Image defects which appear periodically may be caused by failure of rollers. Refer to
<Pitches on images caused by rollers>
which defects appear on the image.
• Check if damp paper is used.
• 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
and determine the cause based on the pitch at
2-93
to remove the dirt from the
Remedy
Refer to the Fig. 2-14 (P2-73)
paper dust cleaning roller.
Perform drum cleaning.
(Refer to "2.1 Drum Cleaning" in Chapter
Clean the filter.
Replace the fuser unit.
Replace the high-voltage power supply PCB
ASSY.
to clean the
5.)
Confidential