Maytag dishwasher PDB2430AWE fills with water and then drains

Here’s how to put it into diagnostic mode.

https://www.youtube.com/watch?v=I1GHfBtt...

Disconnect the power supply from the dishwasher and then remove the lower toe panel. Disconnect the two wires connected to the pressure switch and put tape on the end of the terminals without letting them touch and your dishwasher may operate normally without immediately going into a pump out. If it works, it will clean and operate without problems, but if the issue stems from the pump, I would test the pump's continuity and replace if needed. Another possibility to consider if bypassing the pressure switch doesn't help would be to multimeter test the electronic control board, it could be having issues with the timer aspect. However, if you bypass the switch and it resumes operation, that would be a clear sign that the pump is faulty.