Horn
Pressa 
on the steering wheel pad
to sound the horn.
See also:
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 ...
Heavy-DutyTrailer Wiring Harness Package
For vehicles equipped with heavy duty trailering, the harness connector is mounted in the bumper.
The seven-wire harness contains the following trailer circuits:
• Yellow: Left Stop/Turn Signal
...
Compass
The vehicle may have a compass in the Driver Information Center (DIC). ...