White Spots - Brother FAX-2840 Service Manual

White spots

<User Check>
- When the white spots appear at intervals of 32.5 mm, replace the
- If the same problem occurs after printing a few pages, the adhesive
- When the white spots appear at intervals of 94.2 mm, replace the
Step
Dirt on electrodes of the drum unit
1 and those of the machine
High voltage power supply PCB
2
failure
3 Main PCB failure
Black spots or dirt
<User Check>
- When the black spots appear at intervals of 32.5 mm, replace the
- If the same problem occurs after printing a few pages, the adhesive
- When the black spots appear at intervals of 94.2 mm, replace the
Step
Dirt on electrodes of the drum unit
1 and those of the machine
Dirt on the heat roller
2
Scratch on the heat roller
3
(black spots at intervals of 53.4 mm)
High voltage power supply PCB
4
failure
5 Main PCB failure
toner cartridge with a new one.
of the label or the like, paper powder or dirt may be attached on the
surface of the exposure drum. Wipe off the dirt on the exposure
drum. (Refer to User's Guide, and perform the Drum Cleaning.)
drum unit with a new one.
Cause
toner cartridge with a new one.
of the label or the like, paper powder or dirt may be attached on the
surface of the exposure drum. Wipe off the dirt on the exposure
drum. (Refer to User's Guide, and perform the Drum Cleaning.)
drum unit with a new one.
Cause
2-73
Remedy
Clean the electrodes of the drum unit and
those of the machine. (Refer to
and Fig. 2-11.)
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
and Fig. 2-11.)
Refer to "2-70 How to clean the heat roller"
to clean the heat roller.
Replace the fuser unit.
Replace the high voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
Fig. 2-10
Fig. 2-10
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