My dishwasher has been working great for years but stopped draining a few days ago. I have verified the drain hose is clear, air-gap is clear, hose from air-gap to garbage disposal is clear, and the knockout plug in the disposal has been correctly removed. My thinking is most likely the drain pump needs to be replaced.

The dishwasher does make a slightly different sound than it used to when it enters the drain cycle.

Anyone know of any other diagnosing I can do or other possible problems before I spend the money on a new drain pump?

Thanks in advance.

I knew the knockout plug in the garbage disposal was already out because it had previously drained correctly, and I haven't changed anything related to that. I unhooked the drain hose from the air gap and visually checked the air gap. I then had to pull the dishwasher out to unhook the drain hose from the dishwasher itself and run water through it to verify it was clear.

I'll let you know if the new drain pump makes a difference after I get the part replaced.

I have the same problem (water not draining) since the washer is almost 12 years old I replaced it with a new one, but still the water does not drain. About a month back I have replaced the garbage disposal too. Did I have to do something with the garbage disposal unit?:confused:

Thanks,
Roshan