Horn
Pressa 
on the steering wheel pad
to sound the horn.
See also:
Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously for five days. After five days, OnS ...
Trip Odometer
Press the trip/fuel button until TRIP displays. This display shows the current distance traveled in either kilometers (km) or miles since the last reset for the trip odometer.
Pressing the trip odome ...
Conditions in Which Remote Start Will Not Work
The remote vehicle start feature will not operate if:
○ The key is in the ignition.
○ The hood or doors are not closed.
○ The hazard warning flashers are on.
○ There is an ...