GF82.95-P-3212RDV Emergency Call System Control Unit, Component Description
GF82.95-P-3212RDV Emergency Call System Control Unit, Component Description
MODEL 172.4
- with code (348) Emergency call/Assist system
Shown with code (512) COMAND APS with DVD changer
A2/5 Global positioning system antenna splitter
N123/4 Emergency call system control unit
Location
The emergency call system control unit is located in the trunk under the trunk mat on the crossmember.
Task
^ Realization of vehicle-related services
^ Regulation of priorities via integrated priority management
^ Communication management between vehicle and service center
^ Audio management
^ Display management
^ Fault handling
^ Receive signals
^ Transmit 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 such as navigation data to 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)
The Internet connection (with code (512) COMAND APS with DVD changer) is not controlled via the emergency call system control unit but 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 also 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 if one of the four services with the highest priority is activated by SMS, 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:
- 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 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 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").
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 (S93/3s2), the breakdown assistance button (S93/3s4) and the MB Info button (S93/3s5).
Audio management
- Voice output via the emergency call speaker (H4/48) (except code (810) Sound system) or the center instrument panel speaker (H4/27) (with code (810) Sound system)
- Audio muting (MUTE)
Fault 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 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 memory.
Receive signals
^ Controller Area Network (data bus/CAN bus) (CAN)
^ Direct lines
Controller Area Network (data bus/CAN bus) (CAN)
The emergency call system control unit is a diagnostic CAN subscriber (CAN D). 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
- Operation of the emergency call system button, the MB Info button and the breakdown assistance button
- Wheel speed and yaw rate signals from the Electronic Stability Program control unit (N30/4) (except code (233) DISTRONIC PLUS) or from the Premium Electronic Stability Program control unit (N30/7) (with code (233) DISTRONIC PLUS)
- Vehicle data (for "Initial Summary")
- Diagnostic data (with remote diagnosis)
Direct lines
- Power supply via circuit 30 and circuit 31
- Crash signal from supplemental restraint system control unit
- Signal from hands-free system microphone (A67b1) over COMAND controller unit
- Mobile radio and Internet signals from the multifunction antenna (A28/11) via a coaxial cable
- Global Positioning System (GPS) signals from the multifunction antenna via the Global Positioning System antenna splitter (A2/5) (with code (512) COMAND APS with DVD changer)
- Mobile phone signals from emergency call system antenna (A2/52)
Transmit signals
^ CAN
^ Direct lines
CAN
- Actuation signal for LEDs in the emergency call system button, the MB Info button and the breakdown assistance button
- Internet signals to the COMMAND controller unit
- 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
Direct lines
- Voice output via the emergency call speaker (except code (810) Sound system) or the center instrument panel speaker (with code (810) Sound system)
- Audio mute to COMAND controller unit (except code (810) Sound system or to sound system amplifier control unit (N40/3) (with code (810) Sound system)
- Mobile phone signals to multifunction antenna via coaxial cable
- Mobile phone signals to emergency call system antenna
Design
- Integrated communication module with Bluetooth(R) 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 data relating to 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
^ communication module
Position finding module
The emergency call system control unit calculates the vehicle position with the aid of the built-in position finding module and generates a message to the Service Center or a data telegram ("Initial Summary") in the form of an SMS if necessary.
communication 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"
- After circuit 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.
