I can't tell you which models, but once they go into an error code the Settings Menu may become inaccessible. And if you replace the printhead while...
I would suggest to not let it do firmware with the finisher attached. It could work like the FS534 working instead of the FS536 on the 8 series but
...
You have got me curious. What are you trying to do? The devtank will discard excess developer through the waste port. I would guess about a teaspoon...
I've never seen the official bulletin, but it's no small task. On later production models they installed a new style front cover with holes to access...
If I were to guess, I'd guess that the U021 reset cleared the speed upgrade code, so it won't accept that toner, and it will run at 25ppm. I suspect...
So just to clarify: That line is crossfeed? If yes, start with the simplest of solutions: clean every rubber, metal, or plastic roller thoroughly. I...