See also:

Rear Seats
The vehicle's rear seat has head restraints in the outboard seating positions that cannot be adjusted. Rear outboard head restraints are not designed to be removed. ...

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. ...

Remote Keyless Entry (RKE) System Operation
The Remote Keyless Entry (RKE) transmitter functions work up to 60m (195 ft) away from the vehicle. There are other conditions which can affect the performance of the transmitter. See Remote Keyless ...