External air temperature sensor
Most modern cars offer their passengers a display to show the outside air temperature.
The task of the external air temperature sensor is to measure the air temperature outside of the car. The sensor is commonly located in the front bumper of the car.
The sensor consists of temperature dependent resistor that has a working temperature range between -40 up to +40°C.
In case of a defective temperature sensor the shown outside air temperature will be implausible.
In addition to that the board computer will issue an error code.
As the sensor is outside of the car the most common failure reasons are contamination and corrosion.