Component description for emergency call system control unit - GF82.95-P-3212FQV
MODEL 218 with CODE 348 (Emergency call/assistant system)
Shown with CODE 512 (COMAND APS with DVD changer)
Location
The emergency call system control unit is located in the trunk under the reversible mat on the crossmember.
Task
- Realization of vehicle-related services
- Regulation of priorities via integrated priority management
- Communication management between vehicle and service center
- Display management
- Audio 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. navigation 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 531 (COMAND APS) or with CODE 522 (Audio 20 radio))
The Internet connection is not controlled via the emergency call system control unit, but the COMAND controller unit (A40/3) or via the radio (A2) with CODE 522 (Audio 20 radio).
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.
| 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").
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
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), the breakdown assistance button (S93/6s2) and the MB Info button (S93/6s1).
Audio management
- Voice output via center instrument panel speaker (H4/27)
- Audio mute function (MUTE)
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 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
- CAN
- Direct lines
- Integrated Bluetooth® interface (except CODE 531 (COMAND APS))
- Integrated radio interface for wireless local area network (WLAN) (with CODE 531 (COMAND APS))
CAN
The emergency call system control unit is a diagnostic CAN (CAN D) subscriber. The emergency call system control unit receives signals such as the following 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) (except CODE 233 (DISTRONIC PLUS) and except model 218.374) or from the Premium Electronic Stability Program control unit (N30/7) (with CODE 233 (DISTRONIC PLUS) or model 218.374)
- Vehicle data (for "Initial Summary")
- Diagnostic data (with remote diagnosis)
Direct lines
- Power supply via circuit 30 and circuit 31
- Global Positioning System (GPS) signals from the multifunction antenna via the Global Positioning System antenna splitter (with CODE 512 (COMAND APS with DVD changer) or with CODE 531 (COMAND APS) or with CODE 522 (Audio 20 radio) and with CODE 357 (SD card navigation))
- Crash signal from supplemental restraint system control unit
- Operation of the emergency call system button, the MB Info button and the breakdown assistance button
- Signals from the hands-free system microphone (A67b1) via the audio equipment
- Mobile telephone signals from multifunction antenna via a coaxial cable
- Internet signals from the multifunction antenna via a coaxial cable
- Cellular telephone system and Internet signals from the emergency call system antenna (in the event of poor reception or multifunction antenna failure)
Integrated Bluetooth® interface (except CODE 531 (COMAND APS))
The emergency call system control unit receives Bluetooth® signals for Internet communication which are transmitted by the COMAND controller unit with CODE 512 (COMAND APS with DVD changer) or the radio with CODE 522 (Audio 20 radio) via the Bluetooth® antenna (A2/91).
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 the COMAND controller unit transmits via the W-LAN antenna (A2/83).
Transmitting signals
- CAN
- Direct lines
- Integrated Bluetooth® interface (except CODE 531 (COMAND APS))
- Integrated radio interface for wireless local area network (WLAN) (with CODE 531 (COMAND APS))
CAN
- Internet signals to the audio equipment
- Navigation and other data transmitted by the Service Center ("Remote Information Feed") to the audio equipment
- Status signals to the audio equipment
- Status signals to the instrument cluster
Direct lines
- Actuation signal for LEDs in the emergency call system button, the MB Info button and the breakdown assistance button
- Audio mute function (MUTE) to the audio equipment (except CODE 810 (Sound system) and except CODE 811 (Advanced sound system)) or to the sound system amplifier control unit (N40/3) (with CODE 810 (Sound system) or CODE 811 (Advanced sound system))
- Voice output via center instrument panel speaker
- Mobile phone signals to multifunction antenna via coaxial cable
- Mobile phone signals to emergency call system antenna
Integrated Bluetooth® interface (except CODE 531 (COMAND APS))
- Internet signals to the Bluetooth antenna (with CODE 512 (COMAND APS with DVD changer))
The emergency call system control unit transmits Internet data as Bluetooth® signals to the Bluetooth antenna (with CODE 512 (COMAND APS with DVD changer) or with CODE 522 (Audio 20 radio))
Integrated radio interface for wireless local area network (WLAN) (with CODE 531 (COMAND APS))
The emergency call system control unit transmits Internet data as radio signals to the W-LAN antenna.
Body
- Integrated Internet-compatible communications module with Bluetooth® interface and radio interface for wireless local area network (WLAN)
- 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 via 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 also activated (wake-up); after four days the emergency call system goes into "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.
| Wiring diagram for emergency call system control unit | PE82.95-P-2101-97XAA |