Brother MP-21C Service Manual page 109

Print edges not aligned
Ink splash
Random missing dots
White horizontal streaks
Stained leading edge of print
paper
Check the following:
- The alignment of vertical print lines.
(Use the Service software tool software to check this.)
Check the following components:
- Encoder strip
* If the Encoder strip is not hooked onto the mounting clips
properly, correct it.
- Print head
* If the Print head is not installed securely, correct it.
- Perform purging several times to remove dust or air bubbles
from the nozzles.
- If any cartridges have run out of ink.
- Replace the Print head.
- Replace the Main PCB.
- Replace the Power supply PCB.
- Replace the Head PCB.
- Perform the head cleaning operation several times to
remove dust or air bubbles from the nozzles.
- If any cartridges have run out of ink.
- Replace the carriage PCB.
- Check the connection of the Head FFC CABLE and the
Head FPC cable.
- Replace the Main PCB.
- Check if the Purge unit is attached properly.
- Check the routing of the Waste ink tube.
- Perform the head cleaning operation several times to
remove dust or air bubbles from the nozzles.
- Replace the Print head.
- Check the paper feed-related rollers.
- Check the connection of the Head FPC cable.
- Adjust the amount of line feeding with the Service software
tool software.
Check the following components:
- Head PCB
- Check if paper is catching any other components during
paper eject.
- Clean the nozzle ends of the Print head with a cotton stick,
being carefully not to touch the print head surface.
IV-8