Brother DCP-7030 Service Manual page 55

■ White vertical streaks
Step Cause
Condensation
1
Dirt on scanner
2
windows
Transfer failure
3
Scanner window
4 of laser unit
failure
■ White horizontal streaks
Step Cause
Toner cartridge
electrode
1
connection
failure
Drum unit
electrode
2
connection
failure
User Check
• Clean the scanner windows of the laser unit with a soft lint-free cloth.
(Refer to Fig. 1-6.)
• Replace the toner cartridge with a new one.
• Check the machine's environment. High temperature and high
humidity conditions can cause this problem.
• Damp (wet) paper might be used. Try to change to freshly unpacked
paper.
• Check there is no dust in the gap between the toner cartridge and
drum frame.
Check
Has condensation
occurred inside the
machine?
Is the scanner windows
dirty?
Is the transfer roller
scratched?
Is the problem solved
after replacing the laser
unit?
User Check
• Check that the appropriate media type is selected in the printer
driver.
• The problem may disappear by itself. Try printing multiple pages to
clear this problem especially if the machine has not been used for a
long time.
• The drum unit may be damaged. Replace the drum unit with a new
one.
Check
Are the electrodes on
the toner cartridge and
machine body dirty?
Are the electrodes on
the drum unit and
machine body dirty?
1-37
Result Remedy
Try to print several pages
or leave the machine 2
Yes
hours to allow it to reach
room temperature.
Clean the scanner
Yes
windows.
Replace the drum unit.
Yes
Replace the laser unit.
Yes
Result Remedy
Clean both electrodes.
(Refer to Fig. 1-1, Fig.
Yes
Clean both electrodes.
(Refer to Fig. 1-1, Fig.
Yes
1-2.).
1-2.).
Confidential