The doors will lock automatically when all doors are closed, the ignition is on, and the vehicle is shifted out of P (Park).
If a vehicle door is unlocked and then opened and closed, the doors will lock either when your foot is removed from the brake or the vehicle speed becomes faster than 13 km/h (8 mph).
To unlock the doors:
on the power
door lock
switch.Automatic door locking cannot be disabled. Automatic door unlocking can be programmed. See Vehicle Personalization.
Delayed Locking
Lockout Protection#PIC5491D: OnStar Will Not Power Up - (Oct 8, 2013)
Subject:OnStar Will Not Power UpModels: 2006-2014 GM Passenger Cars and Truckswith OnStar (UE1) Gen7, Gen8, Gen9, or FCP1This PI was superseded to add STID / Station ID for identification. Please discardPIC5491C.Condition/ConcernA concern may be identified on a Gen7, Gen8, Gen9, or FCP1 VCIM as the ...