Our Kenmore dishwasher (665-13793K602) seems to run through it's cycle, but there's no water - the motor just hums. I've checked the float valve and it's not stuck up. My guess is the water line valve is not working or the pump has seized up. The unit is less than 2 years old and the entire pump assemble was replaced less than a year ago (the original was very noisy). Any suggestions on how to trouble-shoot this problem?

Thanks

One way is to remove the water valve, leaving the electrials plugged up, turn on the unit and see if water comes out of the valve (use a cup or towels to catch any water, of course) If you don't get water replace the valve. Part # AP3866788 or 8563405

Nat

You should just have to remove the kick plate.

Also I think you would have to add more than a quart of water to the unit to get it to pump properly. They usually fill till just under the heating element.
With a low water level the pump will cavitate (suck air) and not work correctly.

If you have a meter check across the valve for voltage, when it should be filling.
Should be 120 volts.
If you have voltage then it is either the valve OR the filter screen on the input side of the valve is clogged up.

Remove the valve and check the screen.
If dirty clean it, do not remove it. It is there to keep crud out of the valve which could hold it open and cause a flood.

Also a good idea to drain some water out of your hot water tank once or twice a year. Use the drain or the pressure releif. Let it run till it is clear.