Circuit/System Verification
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.
Ignition ON, observe the scan tool Ambient Air Temperature parameter. The reading should be between -40°C (-40°F) to +88°C (+190°F) and change with air temperature changes.