You probably have a bi-metal spring controlling the door. Pull off inner door panel and check for the bi-metal leaf spring. Make sure the electrical connections are good.
Unplug wires to motor and run dishwasher,check during the entire wash cycle for voltage to it. If none, you probably have a bad timer, or rusted connection to it.You might try spraying the timer with a non-residue spray cleaner and turn the timer. If still bad You will need to call Appliancepartspros to get the timer, your model # is missing in their data base.