2011 Chevrolet Avalanche Owner's Manual - Page 267

Climate Controls Heated Mirrors: For vehicles with heated outside rearview mirrors, the mirrors heat to help clear fog or frost from the surface of the mirror when the rear window defog button is pressed. See Power Mirrors on page 2‑20. 8-9 Sensors There is also an exterior temperature sensor located behind the front grille. This sensor reads the outside air temperature and helps maintain the temperature inside the vehicle. Any cover on the front of the vehicle could cause a false reading in the displayed temperature. The climate control system uses the information from these sensors to maintain your comfort setting by adjusting the outlet temperature, fan speed, and the air delivery mode. The system may also supply cooler air to the side of the vehicle facing the sun. The recirculation mode will also be used as needed to maintain cool outlet temperatures. There is also an interior temperature sensor located next to the steering wheel that measures the temperature of the air inside your vehicle. The solar sensor, located in the defrost grille, middle of the instrument panel, monitors the solar heat. Do not cover the solar sensor or the system will not work properly.