Indicator/Warning Message Description and Operation: OVERSPEED
WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The IPC illuminates the OVERSPEED indicator when the IPC detects that the vehicle speed is more than 120 km/h (75 mph).