We have a Bosch dishwasher that has stopped working. The symptom is a mechanical clicking sound, almost like a gear on a timer being stuck as it tries to move forward.

I've dismantled the door and the sound is definately coming from the main control unit.

What I don't understand is why a control board would be clicking. Is there a mechanical timer in the sealed unit?

Any clues before I spend the $$$ to replace the control unit?

Thanks