Ice Possible
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The IPC illuminates the ICE POSSIBLE message in the driver information center (DIC) when the outside air temperature drops below 4°C (39°F). The IPC receives a class 2 message from the body control module (BCM) indicating the outside air temperature.