[teresastone]

Detergent is still in cup after cycle is complete. Looks like water never even touched it. The door is open on the detergent cup but the detergent is still there.
Ran dishwasher through THREE cycles still the same result. PLEASE HELP!

[PS Staff - Sheila]

It sound like that spray arm may not be moving.

Place the spray arm so it is pointing to wards the door, let the dishwasher fill and start to wash then open the door and see if the spray arm has moved.

There may be a problem with the wash impeller not pushing the water up to the arm to move them.

Are the dishes on the top rack wet?

Here is a link to your dishwasher model MDBTT79AWB.