I have a whirlpool du945pwsb0 which is having issues. I changed the control board on it but the washer still does not work. The reason I changed the control board was because the controls were acting very funny and the cycle would not start. Sometimes the buttons would not change to the selected option. At times I would smack the door to the right of the controls (right over the control board) and the dishwasher would start and cycle through with no issues. Well this eventually stopped working to the point where all the lights work and the selected cycle starts to run but the dishwasher does not spray water. The soap dispenser opens and dries the dishes but is not washing.
I changed the control board but the dishwasher still has the same behavior. I did notice after hitting the start button the dishwasher takes about a minute to start. If I let it run through the cycle it completes but never sprayed water.
Does the unit fill and drain OK?
If yes then remove power from the unit and check the motor windings with a meter, see the tech sheet.
Check the wires from the control board to the motor for continuity.
OK the buzz tells you that there is power getting to the pump.
Do not let it run like this as it will damage the pump.
Your problem seems to be that you are not getting water.
Add a quart of hot water to the unit to ensure the pump does not run while dry.Remove the kick plate and check that the overfill (float) switch (Item 30 in Section 5) is activated.
Sometimes the float can stick in the up position and this disconnects power to the fill valve.
IF OK
Check for 120 volts across the fill valve (Item 16 in Section 5) when it should be filling.
If you have 120 volts.
If OK then I would check the screen filter on the input side of the water valve for a plug. If dirty clean it. Do not permanently remove it from the valve as it is there to keep crud out of the valve which could hold it open and cause a flood.
If it is clean then replace the valve.
If there is no voltage then check for 120 volts across the inlet valve and the overfill switch. Perhaps the overfill switch is shot (not closing).
The float was stuck up as you suggested. I pulled the plastic float up and it came out completely and then i pushed back in. I then noticed the float move freely now. Started the dishwasher and this time it filled up.
And thanks for getting back to us. Now when others search for a similar problem they will see what actually worked instead of just suggestions about what could be the cause.