See also:

Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is moving. Only set it when the vehicle is in P (Park). Press the vehicle information button until PRESS TO CHANGE COMPASS ZONE displays. 2. Find ...

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. ...

Automatic Headlamp System
When it is dark enough outside, the automatic headlamp system turns on the headlamps at the normal brightness, along with the taillamps, sidemarker, parking lamps, and the instrument panel lights. The ...