At wits end with KitchenAid Dishwasher

I have a KitchenAid Dishwasher kdte104ess2. It does not spray water through arms. When I run diagnostic then it comes up with a 6-4 code. I have checked float switch and all seems fine. Fill with water and drains fine. Once in a while it will run properly with spray arms running. 9out of ten it just fills, heats and drains. With nothing in between. Checked for clogs as well and nothing. Could it be control panel or something else ?!?!?!?! HELP PLEASE.

update on machine. I have pulled out machine from under the counter. Ran diagnostic and normal cycle. All Tan perfect with no codes. When I put back into under counter then the pump motor does not run. Wiring???? Been fine for two years before this