A system and method for determining a presence of a mobile device located in a predetermined detection zone within a vehicle may include a plurality of transmitters located within the vehicle, in which each of the plurality of transmitters is configured to transmit an acoustic signal into an acoustic environment within the vehicle, and in which each of the acoustic signals comprises at least one ultrasonic pulse, a mobile device configured to periodically record sounds in the acoustic environment, and a processor configured to determine that a periodically recorded sound by the mobile device comprises each of the acoustic signals transmitted by the plurality of transmitters, determine a location of the mobile device within the vehicle based on the acoustic signals recorded by the mobile device, and determine that the location of the mobile device matches the predetermined detection zone.