WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
Circuit
Description
Signal circuit
The sensor resistance varies with temperature.
Components
B9 Ambient Air Temperature Sensor
P16 Instrument Cluster
The input voltage varies depending on the temperature of the sensor.