Emergency call system control unit, component description - GF82.95-P-3212CWU

MODEL 204.0 with CODE (359) TELE AID emergency call system 

Illustrated on model 204.0 

Location 

The emergency call system control unit is located in the trunk under the trunk mat on the crossmember.

Task 

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

• Authorization (Provisioning)
• Telematic Alarm Identification on Demand (emergency call system) (TELE AID) emergency call (E-call) manual or automatic, incl. police emergency call number "911"
• MB-Info call
• Breakdown assistance (Roadside Assistance)
• Vehicle tracking
• Vehicle remote door unlock
• Vehicle remote door lock

The main task of the emergency call system control unit is to manage communication between the vehicle and the Customer Assistance Center (CAC) via the country-specific mobile telephone network along with forwarding information to the customer when required.

Following activation of one of the following actions, the emergency call system control unit forwards the vehicle position and identification as well as other necessary data to the CAC:

• Crash signal from supplemental restraint system control unit (N2/10), for automatic TELE AID emergency call
• Actuation of emergency call system button (S93/3), for manual TELE AID emergency call
• Actuation of MB-Info button (S93/6s1), for MB-Info call
• Actuation of breakdown assistance button (S93/6s2), for breakdown assistance
• Call to CAC and actuation of trunk lid external operation switch (S88/8), for vehicle remote door unlock
• Call to CAC or triggering of an anti-theft alarm system (ATA [EDW]) alarm, for vehicle tracking

The emergency call system control unit also performs the following tasks:

• Communication management:
  • Priority control
  • Mobile phone function for vehicle-related services over the integrated communication module with Network Access Device (NAD) control
• Audio management:
  • Amplification of audio signals via 5 W audio amplifier (integrated)
  • Output of audio signals via center instrument panel speaker (H4/27)
• Integrated priority management
• Data transfer over diagnostic CAN
• Display management in the Audio/COMAND display (A40/8), in the instrument cluster (A1) or in the listed buttons
• Error handling

The emergency call system control unit can be flashed and configured for the following actions:

• Diagnosis and software update (flashing) via KW-2000 protocol
• Configuration via Management Information Base (MIB)

Discrete inputs 

The emergency call system control unit is supplied with power via the following inputs or it discretely reads in the signals of the following components:

• Circuit 30
• Circuit 31
• Global Positioning System (GPS) signals from multifunction antenna (A28/11)
• Mobile phone signals or data from multifunction antenna
• Crash signal from SRS control unit
• Mobile phone signals or data from emergency call system antenna (A2/52)
• Voice control system microphone (B25/7)
• Emergency call system button
• MB-Info button
• Breakdown assistance button

For vehicles with code (512) COMAND APS with DVD changer, the GPS signals of the multifunction antenna are split by the global positioning system antenna splitter (A2/5) and forwarded to the emergency call system control unit.

For vehicles with code (389) Mobile phone preinstallation with universal interface, USA/Canada and comfort telephony, the mobile phone signals or data of the multifunction antenna are split by the frequency switchover control unit (N96) and forwarded to the emergency call system control unit.

In the event of a multifunction antenna malfunction (e.g. defective because of rollover) the emergency call system control unit automatically uses the emergency call system antenna to transmit mobile phone signals or data.

Discrete outputs 

The emergency call system control unit issues signals via the following outputs to each respective component:

• Center instrument panel speaker
• Audio muting (MUTE):
  • Sound system amplifier control unit (N40/3), with code (810) Sound system
  • "Master control unit", except code (810) Sound system
• Control line to frequency switchover control unit
• Mobile phone signals or data to the multifunction antenna
• Mobile phone signals or data to the emergency call system antenna
• Emergency call system button
• MB-Info button
• Breakdown assistance button

Depending on equipment installed one of the following "master control units" is installed:

• COMAND controller unit (A40/3), with code (512) COMAND APS with DVD changer
• Radio (A2), with code (494) USA version
• Radio, with code (510) Audio 20 with CD changer

Controller Area Network (data bus/CAN bus) (CAN) signals 

The emergency call system control unit is a diagnostic CAN subscriber. The current CAN signals can be found in the current K-matrix.

The emergency call system control unit receives the crash information from the SRS control unit and additionally (redundantly) incl. crash level in the following way:

• Chassis CAN
• Front SAM control unit with fuse and relay module (N10/1)
• Diagnostic CAN

Design 

The emergency call system control unit is designed as follows:

• Integrated communication module with NAD
• Integrated navigation module
• Integrated GPS receiver for position finding (date, time, history and last-known location) for the listed vehicle-related services
• Memory for vehicle-specific data
• Screened metal housing

Function 

The emergency call system control unit has its own microprocessor. A differentiation is made between the 2 subareas of the communication module with NAD and the navigation module. The emergency call system control unit centrally processes all the vital data for the listed vehicle-related services.

The emergency call system control unit uses the installed navigation module to calculate the vehicle position and then generates - if one of the following vehicle-related services has been activated - the data telegram in the form of an SMS:

• TELE AID emergency call, manual or automatic, incl. emergency police assistance number "911"
• MB information call
• Breakdown assistance
• Vehicle remote unlocking

Prioritization 

The emergency call system control unit software processes its routines and commands irrespective of the connected components, i.e. the prioritization of individual tasks is controlled by the emergency call system control unit. These priorities in turn can only be edited and defined over the MIB.

Priority	Services
1	Automatic TELE AID emergency call
2	Manual TELE AID emergency call
3	Vehicle tracking
4	Breakdown assistance
5	MB information call
6	Authorization
7	Vehicle remote unlocking
7	Vehicle remote locking

Communication module with NAD 

The communication module with NAD integrated into the emergency call system control unit is a cellular telephone system transceiver that enables voice and data communication with the CAC over mobile phone frequencies. This supports communication via the two American mobile telephone networks: the analog Advanced Mobile Phone Service (AMPS) network and the digital Code Division Multiple Access (CDMA) network. For data communication in the AMPS network, the communication module with NAD is also equipped with a modem. Listed below are the properties of the AMPS and CDMA networks:

• CDMA Class 3, 800 MHz with 0.2 W transmitting power
• CDMA Class 2, 1900 MHz with 0.1 W transmitting power
• AMPS 800 MHz with 3 W transmitting power
• SMS (line-oriented data transfer (Circuit Switched Data (CSD)), in the CDMA network

Additional communication module with NAD functions are:

• 4 day transmit and receive capability, as soon as an SMS is received, the emergency call system control unit is activated (wake-up); after 4 days TELE AID reverts to the "sleep mode"
• Following activation a self-diagnosis is performed and the result sent to the controller