Bizhub C35P not adding black toner

[altech]

I have a BH C35P that is not adding K Toner into the K I/U, and I have updated FW, replaced the K I/U, and replaced the K toner drive clutch, and replaced the K toner all of which did not fix the problem. Any suggestions?

[B0265]

Replace the black toner sensor.

[EarthKmTech]

as already said, if the toner sensor does not work properly it will never add toner, same as c25.

the same goes if it is contaminated with toner.

It is just an oversized photo sensor which looks into the window on top of the imaging unit directly at the area with a square internal window wiper. (driven by dev roller drive, not drum) If the wiper isnt wiping properly it will never add toner either.