Again that biz(dam)hub 500

[redime]

When you removed the toner add mechanism, you probably removed a screw in the lower right side of it that looks like it needs to come out. It doesn't but when you re-assembled, instead of putting the short screw in that you removed, you put in a normal sized screw and it has stabbed the toner add solenoid coil, shorting it out. I've seen this often after techs troubleshoot a 2403 code.

Seen this as well, a screw holding the solenoid is too long and stabbing into the coil.

TCR sensor been replaced?

HVPS?

Might sound stupid, but did you try a new toner bottle?

[suomi]

The toner bottle is warped.

[mo0651]

Before replacing any more boards or motors. Inspect the solenoids that run the toner supply motors in the back of the machine. Take them out and look carefully. We had one that had too long of a screw holding a plate and the screw pierced the protective skin on the solenoid. You can see the indentation. This was a factory installed screw. Took out 2 boards before we even had a clue. It's worth a look.Especially with a lot of toner related errors.