mESSAGE WASTE TONER FULL. Replaced process unit did not clear. Flashed system Firmware no help. Any Suggestions.

From the book;
After replacing the process unit, turn the
power switch off and then on. If the problem
cannot be solved, replace the waste
toner sensor or the engine PWB.

That's all I can think of.
Gene Y.

you might get more responses in the right Forum, I don't know just a thought.