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

MODEL 204 with CODE 348 (Emergency call/assistant system) 

Shown on model 204.3 with CODE 512 (COMAND APS with DVD changer) 

Location 

The emergency call system control unit is located behind the seats in the trunk.

Tasks 

• Realization of vehicle-related services 
• Regulation of priorities via integrated priority management 
• Communication management between vehicle and service center 
• Audio management 
• Display management 
• Error handling 
• Receive signals 
• Transmitting signals 

Realization of vehicle-related services 

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

• Authorization ("provisioning")
• Manual or automatic emergency call
• MB information call
• Roadside assistance
• Notification in the event of antitheft alarm ("Anti Theft Notification")
• Vehicle tracking
• Vehicle remote unlocking
• Vehicle remote locking
• Remote diagnosis ("Remote Diagnosis")
• Transmission of vehicle position ("Vehicle Locator")
• Notification of a certain speed being exceeded ("Speed Alert")
• Notification if a certain area has been reached or left ("Geo Fencing")
• Transmission of information (e.g. map data) to the vehicle ("Remote Information Feed")
• Transmission of updates to vehicle ("Remote Update")
• Visual and acoustic vehicle recognition ("Flash Lights and Sound Horn")
• Internet connection (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)))

The Internet connection (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation))) is not controlled via the emergency call system control unit but via the COMAND controller unit (A40/3).

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 short message service (SMS) capability are executed by SMS if one of the four services with the highest priority is activated and the remaining connection resources are released for the prioritized service.
• Services without SMS capability or an Internet connection are terminated if one of the four services with the highest priority is activated and the connection resources are released for the prioritized service.
• The remote diagnosis has its own data channel, and can also be carried out for every other service.
• The four services with the highest priority are executed if no service with a higher priority is active.

Services with SMS capability are:

• Tracking ("stolen vehicle tracking")
• Vehicle remote unlocking
• Vehicle remote locking
• Notification of a certain speed being exceeded ("Speed Alert")
• Notification if a certain area has been reached or left ("Geo Fencing")
• Visual and acoustic vehicle recognition ("Flash Lights and Sound Horn")

The four services with the highest priority are listed below.

Priority service

1. Automatic emergency call
2. Manual emergency call
3. Breakdown 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 via the integrated communication module 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").

Audio management 

• Voice output via center instrument panel speaker (H4/27)
• Audio muting (MUTE)

Display management 

Management of the functional displays on the Audio/COMAND display (A40/8), in the instrument cluster (A1), in the emergency call system button (S93/3), in the breakdown assistance button (S93/6s2) and in the MB-Info button (S93/6s1).

Error handling 

After activating circuit 15R, the emergency call system control unit performs a self-test (approx. 8 to 10 s). If the self-test is successful, the emergency call system is then ready for operation.

In the event of a fault, a fault message is displayed on the instrument cluster, depending on the fault type, and the red light-emitting diodes 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 memory.

Receive signals 

• CAN 
• Bluetooth® 
• Direct lines 

CAN 

The emergency call system control unit is a diagnostic CAN (CAN D) subscriber. The emergency call system control unit receives the following signals from the front SAM control unit with fuse and relay module (N10/1) via diagnostic CAN:

• Crash information from the supplemental restraint system control unit (N2/10) (redundant), including crash level
• Wheel speed and yaw rate signals from the Electronic Stability Program control unit (N30/4)
• Vehicle data (for "Initial Summary")
• Diagnostic data (with remote diagnosis)

Bluetooth® 

• Internet signals from the Bluetooth antenna (A2/91) (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)))

Direct lines 

• Power supply via circuit 30 and circuit 31
• Crash signal from supplement restraint system control unit
• Signal from hands-free system microphone (A67b1) via COMAND controller unit
• Operation of the emergency call system button, the MB-Info button and the breakdown assistance button
• Mobile phone signals from the multifunction antenna (A28/11) via a coaxial cable (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)) also Internet signals)
• Global positioning system (GPS) signals from the multifunction antenna, on vehicles with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)) via the global positioning system antenna splitter
• Mobile phone signals from the emergency call system antenna (A2/52)

Transmitting signals 

• CAN 
• Bluetooth® 
• Direct lines 

CAN 

• Navigation data and other data transmitted by the Service Center ("Remote Information Feed") to the COMAND controller unit
• Status signals to the COMAND controller unit
• Status signals to the instrument cluster

Bluetooth® 

• Internet signals to the Bluetooth antenna (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)))

Direct lines 

• Actuation signal for LEDs:
  • Emergency call system button
  • MB-Info button
  • Breakdown assistance button
  • Voice output via center instrument panel speaker
  • Audio mute (MUTE) to the COMAND controller unit (except CODE 810 (Sound system))
  • Audio mute (MUTE) to the sound system amplifier control unit (N40/3) (with CODE 810 (Sound system))
  • Mobile phone signals to the multifunction antenna via a coaxial cable (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)) also Internet signals)
  • Mobile phone signals to the emergency call system antenna (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)) also Internet signals)

Body 

• Integrated communication module with Bluetooth® and Wireless Local Area Network (WLAN), with Internet capability
• Integrated locating 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
• Buffer for navigation and other data that is transmitted to the vehicle
• Plastic housing

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 
• Communications module 

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 over mobile phone frequencies. Communication takes place via the digital Code Division Multiple Access (CDMA) network. Other functions of the communication module are:

• Four day transmission and reception capability, as soon as an SMS is received, the emergency call system control unit is activated (wake-up); after four days the emergency call system reverts to the "sleep mode"
• Following terminal 15R ON, a self-test is performed

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

N123/4

PE82.95-P-2101-97FAA