Use this service manual to see if you can put the machine into a test/diagnosis mode. Your model is covered at the end.

I am thinking the problem is either your membrane switches or control unit, more like the membrane but since both of these are expensive parts see if you can get a diagnosis from the test.

Also check to make sure you are getting 120v to each side of the connection block, and 120v to the control board.

http://www.servicematters.com/m...ibrary/docs/16023110.pdf