Horn
Press 
on the steering wheel pad to sound the horn.
See also:
Armrest Storage
Vehicles with a rear seat armrest have two cupholders. Pull the armrest down from the rear seatback to access the cupholders. ...
Onstar.com
The website provides access to account information, manages the OnStar subscription,
and allows viewing of videos of each service. Get subscription plan pricing and
sign up for OnStar Vehicle Diag ...
Tire Rotation
Tires should be rotated every 12 000 km (7,500 mi). See Maintenance Schedule on page 11‑3.
Tires are rotated to achieve a uniform wear for all tires. The first rotation is the most important.
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