Outside Air Temperature Display
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
This diagnostic procedure applies to serial data outside air (ambient) temperature displayed in the instrument panel cluster (IPC). The IPC displays the engine coolant temperature from serial data received from the HVAC module. The HVAC module process the signal formation from the ambient air temperature sensor.