Charlie Miller and Chris Valasek demonstrated the attack by hacking a Jeep Cherokee equipped with the Uconnect system. The Uconnect is the connected car system chosen by Fiat Chrysler for its vehicles in the US market. This system allows the owners of the connected cars to interact with the vehicle remotely, it uses the Sprint cellular network to remain connected to the Internet. Car owners can dialog with their car by simply using their Smartphone, typical operation allowed are remote engine start, querying the vehicle to obtain the vehicle’s location, and activating anti-theft features.”]
Source: http://securityaffairs.co/wordpress/38739/hacking/connected-car-hacking.html