Can I clean out a GE dishwasher drain pump?
GE dishwasher won’t drain.
Washer is washing, but doesn’t drain.
During drain cycle you hear a hum, but no water is flowing into the garbage disposal.

Troubleshooting:
Two common problems:  1. Drain hose is blocked at the garbage disposal or anti-siphon air gap connection.  2.  Something is stuck in the drain pump so that the impeller blades can't turn.  That is why you hear a hum, but no water flows.  The drain pump has a magnetic AC induction motor of about 45 watts and is unlikely to burn out.

Unplug dishwasher power. 
Get a large pan.  A plastic pan that you use to drain your motor oil into is about the right size.
Place the pan on the floor in front of your sink cabinet.
The pan should be lower than the bottom of the inside of dishwasher.
Disconnect the drain hose that goes to the air gap or garbage disposal.
If your line is not plugged up, water will flow out of the dishwasher into the pan.
If water flows out of the dishwasher into the pan your drain pump is not working.

Pull the dishwasher out far enough to turn it on it's side.
In many installations you will be able to slide the dishwasher out far enough to turn it on it's side without disconnecting the hot water inlet hose.  Be sure to turn the hot water valve under the sink off.

Fixing the drain pump:

The drain pump is basically dangling from a wire hanger.
Disconnect the hoses and AC wires and remove the pump.
The impeller housing cover is held on by three torx type screws.
Remove the cover and check the impeller blades.  Often you will find a foreign
 object such as piece of glass or china chip that is stopping the impeller blade.  Remove the object and reassemble the pump.

Put everything back together.  Plug in the dishwasher and turn the hot water back on.
Select the “Rinse Only" mode.  Press Start/Reset button.  Wait until you hear the dishwasher washing.  The press the Start/Reset button again.  The dishwasher will stop after a few seconds and hopefully start draining.

Thousands of dishwasher drain pumps have been unnecessarily replaced because a small piece of junk was stuck in the impeller blades.
(Note:  If you don't have a Torx bit go to your local Harbor Freight or hardware store and buy a small set of bits.  Much cheaper than a pump and you will have them for future projects.)