See also:

Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF in each shift lever position. • The ignition should turn to LOCK/OFF only when the shift lever is in P (Park). †...

Transmission
Electronic Range Select (ERS) Mode ERS mode allows you to choose the top-gear limit of the transmission and the vehicle's speed while driving downhill or towing a trailer. The vehicle has an electro ...

OnStar Mobile App
With an iPhone® or Android™-based mobile device, an OnStar mobile app can be downloaded. The vehicle can be remote started, if equipped, or the doors can be unlocked from anywhere there is cell pho ...