Transmission Temperature Sensor/Switch: Description and Operation

LOCATION

The switch is located in the transmission to radiator cooling line.

PURPOSE

The transmission thermo-switch used on automatic transmission applications, opens when the fluid temperature is above 273°F (134°C). With the switch open the controller will not allow the transmission to shift into overdrive. If the switch opens when the transmission is in overdrive it will downshift. Once the switch opens, it will not close until fluid temperature drops to 240°F (116°C).