Connect a wire between the thermistor input terminals on the starter. Thermistor circuits work by looking for the resistance to increase, which can also mean an open circuit. So by putting a jumper wire between the terminals, you are emulating a low resistance circuit, which should be interpreted by the trip unit as a cold thermistor; good to go If it still displays “Tripped”, the circuit is damaged internally and is unlikely repairable without replacing whatever control board it is in.