Vehicular emergency message system with automatic periodic call-in

摘要

A vehicle user can request emergency or roadside assistance from a response center by activating a button in the vehicle. The global positioning system is used to continuously store the vehicle location. A cellular telephone network is used to contact a response center and transfer a data string via modem containing information to assist the response center in acting on the request. The vehicle installed system initiates an automatic call-in to the response center if the elapsed time since the last successful connection with the response center is greater than a predetermined time. Data is transmitted during the automatic call-in that identifies the vehicle and verifies to the response center that a particular system is operative.