I have a Frigidaire Dishwasher Model#FDB2510LCC1 that the buttons have stopped working. When you push normal wash it automatically kicks the selection to lower rack wash and then you can't stop it. You have to kill the power source to it to cut it off. Once you cut the power back on the screen flashes PF. After you open and close the door that goes away. I tried starting it again and the same thing happens. Any suggestions on what this might be?