See also:

Battery Power Protection
The battery saver feature is designed to protect the vehicle's battery. To prevent battery discharge while driving, the following systems are reduced automatically in two stages and then turned off: ...

OnStar Overview
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic Services. The OnStar system s ...

Horn
Press near or on the horn symbols on your steering wheel pad to sound the horn. ...