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Replacement parts for GE GSD5800G00WW | AppliancePartsPros.com

dishwasher does not draing. Water left on bottom after cycles.
Does it drain at all or is it just not draining enough?
Does the solenoid on the left hand side of the main motor/pump assembly activate (plunger pulled down) when the unit goes into drain?
Does the unit wash OK and just the drain is the problem?
If it is not draining fully a common problem is the Piston and Nut valve at the back of the unit under the slotted cover.

Can I remove the smaller pump and have it tested?
You can often feel if the drain pump is running, just be careful that you do not touch the electrical contacts.
You could check it while it is in the unit. Remove the wires from it and check it's winding for continuity. If it is open (infinite ohms) it is toast.
Note this does not totally rule out this pump as the problem.
You could also remove it from the unit, put a line coed on it and check if it runs.