Kenmore Dishwasher Keeps Washing

Hi I have a Kenmore Dishwasher serial number 665-16354300.The dishwasher keeps running on the wash cycle, have to manually stop it or it runs continuously. Any ideas?

Here are your parts
Replacement parts for 665-16354300 models | AppliancePartsPros.com

Here is a tech sheet, see the attachment.

As you can see from the tech sheet it could be that the unit is trying to achieve a water temperature set point but is not getting there.

Could be a bad heater, high-limit thermostat, thermistor or control board.
I am assuming that every thing looks normal.

Try a cycle where no heat is require. Does it now complete t he cycle?
If yes then the above is probably happening.

What is the Thermister? What does it do?

It is a solid state device that changes resistance with temperature (lowers resistance as temperature rises).

Tells the unit what the actual temperature is.