Horn
Pressa 
on the steering wheel pad
to sound the horn.
See also:
OnStar®
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. See OnStar Overview on pag ...
Overheated Engine Protection Operating Mode
This emergency operating mode lets the vehicle be driven to a safe place in an emergency situation. If an overheated engine condition exists, an overheat protection mode which alternates firing groups ...