Embodiments relate to a method for accessing a functionality of a vehicle via a mobile device. The method includes sending, using a first radio access technology, RAT, a ranging intent message from the mobile device to the vehicle; initiating, by the vehicle and using a second RAT, a ranging session for localizing the mobile device upon receipt of the ranging intent message; and upon initiating the ranging session, sending a ranging response message from the vehicle to the mobile device using the first RAT, the ranging response message indicating whether the mobile device is inside or outside at least one operational localization range of the vehicle.