Operation CHARM: Car repair manuals for everyone.

Cabin Temperature Sensor / Switch: Description and Operation

The inside air temperature sensor is a temperature sensitive resistor like the outside temperature sensor; as inside air temperature increases, resistance decreases and as inside air temperature decreases, resistance increases.

A hose connected to the inside air temperature sensor continually draws passenger compartment air over the sensor, increasing the accuracy of the temperature reading.

The heater and A/C programmer monitors the inside air temperature signal and uses this information to help determine command signals.