Brother MFC6800 - Page 149

6-22
Trouble Action to be taken
(3) Light At the scanner
Check the following components:
- CCD unit
- Main PCB
At the printer side
 Replace the toner cartridge with a new one and print 4 to 5 pages.
If the problem persists, proceed to the next step.
 Remove the toner cartridge and start printing. If printing takes
place, clean the toner sensors (LED and light-receiver), check the
sensor harnesses, and then replace the toner sensor PCBs.
 Clean the high-voltage contacts for the transfer roller on the drum
unit, main cover, and high-voltage power supply PCB. (Contacts
in the illustration given on page 6-28)
 Clean the high-voltage contacts for the developer roller on the
drum unit, main cover, and high-voltage power supply PCB.
(Contacts
in the illustration given on page 6-28)
 Clean the grounding contacts on the drum unit, gear drive unit,
and main cover. (Contacts
and in the illustration given on
page 6-28)
 Check the connection of the high-voltage power flat cable on the
main PCB and high-voltage power supply PCB.
 Replace the drum unit.
 Replace the high-voltage power supply PCB.
 Replace the main PCB.
 Replace the laser unit.
(4) Dark At the scanner
Check the following components:
- CCD unit
- Main PCB
At the printer side
 Slide the wire cleaner to clean the corona wire inside the drum
unit.
 Clean the high-voltage contacts for the grid and charger on the
drum unit, main cover, and high-voltage power supply PCB.
(Contacts
and in the illustration given on page 6-28)
 Replace the toner cartridge.
 Replace the drum unit.
 Replace the high-voltage power supply PCB.
 Replace the main PCB.