The emergency call system control unit (N123/4) uses its own microprocessor. The microprocessor is divided into two main areas, the telephone module and the navigation module. The emergency call system control unit (N123/4) is the central processor of all important data for a Telematic Alarm Identification on Demand (emergency call system) (TELE AID) emergency call. With the aid of the integrated navigation module, the emergency call system control unit (N123/4) calculates the vehicle position, and in the event of emergency call it generates the emergency call telegram in the form of an SMS.
The crash data are received by the restraint systems control unit (N2/7) over a serial interface.
The emergency call system control unit (N123/4) can be diagnosed through the central gateway control unit (N93) with STAR DIAGNOSIS via a diagnosis bus.