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Component Description For Emergency Call System Control Unit - GF82.95-P-3212GNU

Model 166 as of model year 2016 up to model year 2017 with code 348 (Emergency call/assistant system) 

Model 292 up to model year 2017 with code 348 (Emergency call/assistant system) 

Shown on MODEL 292 

G14136979Courtesy of MERCEDES-BENZ USA

Location 

The emergency call system control unit is located underneath the left rear seat

Tasks 

The emergency call system control unit has the following tasks:

Realization of vehicle-related services 

The emergency call system control unit enables the following vehicle-related services to be realized:

IMPORTANT The Internet connection is not controlled through the emergency call system control unit, but rather through the audio equipment.

IMPORTANT Via the mobile radio connection to the Service Center the emergency call system control unit also receives the trigger signal for the "Remote Start" function (for pre-entry climate control) which the customer transmits via the mobile phone to the service provider The "Remote Start" function starts the engine on a parked and locked vehicle (windows and doors closed) and after a limited period it switches it off again to enable the "Load Mode" to achieve a pre-entry climate control of the A/C system The emergency call system control unit forwards the triggering signal via the diagnostic CAN (CAN D) to the electronic ignition lock control unit (N73)

IMPORTANT The emergency call system control unit is not used for regular telephone calls.

Regulation of priorities via integrated priority management 

The emergency call system control unit can manage a voice or data connection and an SMS connection at the same time. The data connection can be used by several services simultaneously by means of transmitting data packets at staggered times. The priority management is based on the following principles:

Services with SMS capability are:

The four services with the highest priority are listed in the following table.

Priority Service
1 Automatic emergency call
2 Manual emergency call
3 Roadside assistance
4 MB Info

Communication management between vehicle and service center 

The emergency call system control unit controls communication between the vehicle and the Service Center through the integrated communication module, the antenna connection and the mobile telephone network and establishes a voice connection with the driver if necessary. In many cases (e.g. breakdown assistance, MB Info call) the connection setup with the Service Center also includes the transmission of an SMS containing the vehicle position, identification data and other vehicle data ("Initial Summary").

In the event of a malfunction in the multifunction antenna (A28/11) or if reception is poor, the communication module integrated into the emergency call system control unit automatically transmits and receives the mobile phone signals via the emergency call system antenna (A2/52).

Display management 

The emergency call system control unit actuates the function-specific displays in the following components:

Audio management 

Audio management encompasses the following functions:

Error handling 

Following activation of circuit 15R, the emergency call system control unit then runs a self-diagnosis (approx. 8 to 10 s). If the self-diagnosis test is successful, the emergency call system is then operational. In the event of a fault, a fault message is displayed on the instrument cluster, depending on the fault type, and the two red light-emitting diodes (LED) in the emergency call system button are permanently actuated. Depending on the fault type, the fault is also stored in the emergency call system control unit's fault memory.

Receive signals 

Direct lines 

CAN 

The emergency call system control unit is a diagnostic CAN user, and it receives, for example, the following signals over this CAN connection from the electronic ignition lock control unit:

Integrated radio interface for wireless local area network (WLAN) (with CODE 531 (COMAND APS)) 

The emergency call system control unit receives radio signals for Internet communication which are sent by the COMAND controller unit (A40/3) over the WLAN antenna (A2/83).

Integrated Bluetooth® interface (except CODE 531 (COMAND APS)) 

The emergency call system control unit receives Bluetooth® signals for Internet communication which the radio (A2) forwards over the Bluetooth® antenna (A2/91).

Transmitting signals 

CAN 

The emergency call system control unit sends the following signals via diagnostic CAN to the electronic ignition lock control unit, for example:

Direct lines 

The emergency call system control unit transmits the following signals over direct lines:

Integrated radio interface for wireless local area network (WLAN) (with CODE 531 (COMAND APS)) 

The emergency call system control unit sends Internet signals to the WLAN antenna.

Integrated Bluetooth® interface (except CODE 531 (COMAND APS)) 

The emergency call system control unit sends Internet signals to the Bluetooth® antenna.

Body 

Function 

The emergency call system control unit centrally processes all the vital data for the listed vehicle-related services. The emergency call system control unit has its own microprocessor. A distinction is made between the following subareas:

Position finding module 

The emergency call system control unit uses the installed positioning module to calculate the position of the vehicle and, if necessary, generates a message to the Service Center or a data telegram ("Initial Summary") in the form of an SMS.

Communications module 

The communication module integrated into the emergency call system control unit is a mobile phone transceiver enabling voice and data communication with the Service Center via mobile phone frequencies. Communication takes place via the digital Code Division Multiple Access (CDMA) network. Other functions of the communication module are:

IMPORTANT In the event of insufficient reception or failure of the multifunction antenna (e.g. defect caused by rollover), the emergency call system control unit automatically uses the emergency call system antenna to receive and transmit the mobile radio signals.

  Wiring diagram for emergency call system control unit   PE82.95-P-2101-97NBA