Horn
Press 
on the steering wheel
pad to sound the horn.
See also:
Empty Directory or Folder
If a root directory or a folder exists somewhere in the file
structure that contains only folders/subfolders and no
compressed files directly beneath them, the player
advances to the next folder ...
Cellular and GPS Antennas
Avoid placing items over or near the
antenna to prevent blocking cellular
and GPS signal reception. Cellular
reception is required for OnStar to
send remote signals to the vehicle. ...
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 sy ...