(solved) Brother DCP-J125 not printing

[Lanzi]

I bought my parents a brother printer (ink), since they have Linux support, which my parents use for their homecomputer.
They do not print a lot, about 1-5 pages a month. They mainly use the copy option, where you put a sheet of paper on the printer and get a copy without need to turn on the computer.
For some weeks now, the printer does not print any black... onyl the colors - I suppose that this a hardware problem since th same error occours with the copy mode.

What can I do?

[Lanzi]

I found a solution by myself... There is a servicemenu availble, where I can clean the head. It seems to work!