This has been a gradual failure to print just the black. I have done 3 cleaning cycles, over multiple days, this worked a little but used quite a bit of ink. Then I used a syringe kit with cleaning fluid and paper towels under the head. Made a bit of a mess and pulled out a bunch of color ink at the same time. That did help, I got back about 90% of the print range. However it quickly failed again to 0%. All I have used in this is Brother Ink.
Can the print head removed more a through manual cleaning? What happens to the ink used in the self cleaning operation?