Brother MFC6800 - Page 150

6-23
Trouble Action to be taken
(5) Black and blurred vertical
stripes or band
At the scanner
Check the following components:
- CCD unit
At the printer side
 Clean the paper path which may be contaminated with toner.
 Slide the wire cleaner to clean the corona wire inside the drum
unit.
 Make sure that the wire cleaner is returned to its home position.
 Replace the toner cartridge.
 Replace the drum unit.
 Replace the heat-fixing unit.
(6) Black vertical streaks on gray
background
At the printer side
 Clean the laser beam window (glass) on the laser unit.
 Replace the laser unit.
(7) Black and blurred horizontal
stripes
At the printer side
 Slide the wire cleaner to clean the corona wire inside the drum
unit.
 If they appear at 94-mm or 17-mm intervals, replace the drum
unit.
 If they appear at 54-mm intervals, replace the heat-fixing unit.
 Replace the high-voltage power supply PCB.
(8) Horizontal lines At the printer side
 Check the connection between the right end of the paper feed
roller and the grounding wire. (Contact
in the illustration
given on page 6-28.)