Black Spots - Brother DCP-7030 Service Manual

■ Black spots

Step Cause
Toner attached
on the develop
1 roller
Scratch and Dirt
on the exposure
2
drum
Drum unit
3 connection
failure
Scratch and Dirt
on the heat roller
4
HVPS PCB
5 failure
Main PCB failure Is the problem solved
6
■ Black band
User Check
• Damp (wet) paper might be used. Try to change to freshly unpacked
paper.
• Toner may be empty. Replace the toner cartridge with a new one.
• If the problem is not solved after printing a few pages, the drum unit
may have glue from label stuck on the exposure drum surface.
Refer to the previous
• The drum unit may be damaged. Replace the drum unit with a new
one.
Check
Are the black spots at
40.6 mm (develop roller
circumference)
intervals?
Are the black spots at
75.0 mm (exposure
drum circumference)
intervals?
Are the electrodes on
the drum unit and
machine body dirty?
Are the black spots at
78.5 mm (heat roller
circumference)
intervals?
Is the problem solved
after replacing the
HVPS PCB ASSY?
after replacing the main
PCB ASSY?
User Check
• Clean the inside of the machine and the corona wire in the drum
unit. If the same problem occurs after cleaning, replace the drum
unit with a new one.
• The paper tray ground terminal located in the machine body may be
dirty. Clean the contact with a dry cloth.
1-40
page, and wipe it off gently with a cotton swab.
Result
This problem will
disappear by printing
Yes approximate 10 pages. If
the same problem occurs,
replace the toner cartridge.
Replace the drum unit.
Yes
Clean both electrodes
Yes (Refer to
Replace the fuser unit.
Yes
Replace the HVPS PCB
Yes ASSY.
Replace the main PCB
Yes ASSY.
Remedy
Fig. 1-1, Fig. 1-2.).
Confidential