Updated: Whirlpool ADP 5340 continuously drains and stops

I have a seven year old Whirlpool ADP 5340 dishwasher that is generally used only once every week or two. It was fine until a few months ago at which time it started acting up, first occasionally and now always.

Here’s what happens: After I pick (any) program and push the start button, it drains for a second or so, then stops, the start light and program light go off, they then turn on again and it drains again for a second or so, then off again, then on again — and so on forever. (At the beginning it would eventually settle down and start to wash.)

I have checked that there is water supply at the faucet. The inlet hose has a solenoid valve at the connection to the faucet. I have NOT yet checked that valve (I’m not quite sure how to check it.) I also pulled the bottom panel off of the dishwasher and made sure that the styrofoam float which I figure is there to protect against water spills — was not stuck. Everything else looked good but I did not do any other checks yet.

Any ideas would be helpful. Thanks in advance!

Update: I checked the inlet valve at the faucet — opens the water when I put on 220V. During this on/off cycling of the drain pump the voltage from the controller to the valve is only 38V AC. This may mean that the controller is gone. But — maybe it’s one of the other valves/sensors etc.

Thanks to anyone for any thoughts.