My Kitchenaid Superba KUDS01FLSS5 only operates intermittently and sometimes not at all. Starting up is not the problem but it cuts out during operation. I haven't experimented to see if this happens on all the cleaning modes but it does suffer this problem on "Normal" and "Quick Clean Up."

Opening and closing the door sometimes gets it to start back into the cycle which makes me think the door switch might be the issue?
Another possibility could be the heating element which has significant calcium build up on it and also a discolored spot that makes me wonder if it is cracked and therefore not working. I have confirmed that the water entering the dishwasher is 110 F but anytime the I check the water temp inside it appears less than 110 F and the element is not hot to the touch.

When this dishwasher heats the water does it do it based on a timer or does it measure the actual water temperature to confirm the 120 F setpoint is reached before continuing?

Can I fool it by opening the washer up and pouring in boiling water to bring it over 120 F. If I then close the door it continue on it's cycle?

Other strange performance characteristics are: the lights seem to illuminate based on door position, for example: with the door opened pass 45 degrees the clean mode LED is on, then as the door is shut the LED goes off. After 10 minutes or so the cycle might kick back in.

Back when this Dishwasher was bought and under warranty it had two new boards put in it as the were 'frying' eventually the service tech moved the unit further out from under the cabinet and the boards stopped over heating. Since then it's been reliable (4 years) until now.
Sorry for the epic. Thoughts?