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Replacement parts for General Electric PDW7800J10WW Dishwasher | AppliancePartsPros.com

Could be a problem with the flood (overfill) switch (Item 308 in Section 1).

Check that the switch is being activated re: the float is not stuck in the up position.
If it is up then remove it and clean it, often crud can get in or grow here.
If OK
Check across the water solenoid for 120 volts when it should be filling.
If there is 120 volts then either you have a bad replacement valve or there is a problem with your water supply.
If there is no voltage, check across the overfill switch.
If there is voltage here replace the switch as it is not closing.
If no voltage across the switch check for voltage across the water valve/overfill switch combo, they are wired is series.
If no voltage here, remove the power from the unit and check the wires from the control board to the valve/switch combo for continuity, might be a broken wire.
If OK then I would say you have a control board problem.

A quick way to check the overfill switch if you do not have a meter is to remove the wires from the switch and short them together. Tape them so they cannot short to anything else. Be sure to remove power to the unit when doing this. Then give the unit a try.