Hobart dishwasher

bad thermostat or contactor

You are in luck, the LXI series are easy to troubleshoot. Be carefull of the high voltages present.
If you open the top drawer to expose the control and relay boards you can see the status of everything. You will need a small magnet placed in the drawer, on the door switch in the front right corner to make it think everything is closed. Make sure the door remains closed or you will get very wet.
If the bottom rinse arm is spinning non stop, it could be the water valve has not closed, or the boster is stuck in heat mode. There are LED's on both boards to show status. If the light is on, it is active.
The LXi gives two temperature readouts, wash and rinse. If its constantly flowing water, the booster will never recover to the set point of 186. Fix the flow first and see if the temp poroblem goes away.
Golder rule of trouble shooting. If you have more than one fault, and you know how to fix one of them , do it first and then re test