Brother DCP 8040 - B/W Laser - All-in-One Service Manual page 245

CHAPTER 6 TROUBLESHOOTING
I-9 White vertical streaks
Possible cause
Dirt on the CCD.
Transfer failure
Condensation
I-10 White horizontal stripes
Possible cause
Developing bias
contact failure
User Check
(1) Try to wipe the scanner window with a soft cloth.
(2) The toner cartridge may be damaged. Install a new toner cartridge.
(3) Check the machine's environment. High temperature and high humidity
conditions can cause this problem.
(4) Damp (wet) paper might be used. Try to change to freshly unpacked paper.
Step Check
1 Is there any dirt on that?
2 Is the transfer roller scratched?
3 Has condensation occurred
inside the machine?
User Check
(1) Check the paper used meets the recommended paper specifications. A rough
surfaced paper, damp paper or thick media can cause the problem.
(2) Check that the appropriate media type is selected in the printer driver.
(3) 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.
(4) The drum unit may be damaged. Install a new drum unit.
Step Check
1 Are the developing bias
contacts between the machine
and toner cartridge dirty?
Result
Yes Replace the CCD.
Yes Replace the drum unit.
Yes Try to print several pages or
leave the machine 2 hours to
allow it to reach room
temperature.
Result
Yes Clean the electrodes
at both sides.
6-42
Remedy
Ground
Remedy
contacts
(4)