P82.95-3025-79
A1 | Instrument cluster | N2/10 | Supplemental restraint system control unit | S93/6s1 | MB-Info button | ||
A2 | Radio (with CODE 523 (MB Audio 20 radio) or CODE 510 (Audio 20 with CD changer)) | N10/1 | Front SAM control unit with fuse and relay module | S93/6s2 | Breakdown assistance button | ||
A2/5 | Global Positioning System antenna splitter (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation)), with CODE 508 (Navigation box preinstallation) or CODE 509 (Navigation box)) | N10/2 | Rear SAM control unit with fuse and relay module | CAN A | Telematics CAN | ||
A2/52 | Emergency call system antenna | N30/4 | Electronic Stability Program control unit | CAN B | Interior CAN | ||
A28/11 | Multifunction antenna | N40/3 | Sound system amplifier control unit (with CODE 810 (Sound system)) | CAN D | Diagnostic CAN | ||
A40/3 | COMAND controller unit (with CODE 512 (COMAND APS with DVD changer) or CODE 527 (COMAND APS with single DVD drive (with navigation)) or CODE 528 (COMAND incl. DVD changer)) | N73 | Electronic ignition switch control unit | CAN E | Chassis CAN | ||
A40/8 | Audio/COMAND display | N123/4 | Emergency call system control unit | LVDS | Low voltage differential signal | ||
A67b1 | Hands-free system microphone | N125/3 | AMG Performance Media control unit (model 204.0/2/3 with CODE 255 (AMG Performance Media)) | MOST | Media Oriented System Transport | ||
H4/27 | Center instrument panel speaker | S93/3 | Emergency call system button |
Function requirements, emergency call system, general
Terminal 30
Transport mode not active
Each vehicle-related service is authorized separately
The communication module of the emergency call system control unit is configured with the telephone number of the relevant service provider
The vehicle owner is registered and authorized at the Service Center
Emergency call system, general
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")
Tracking ("stolen 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 emergency call system control unit is not used for regular telephone calls.
The emergency call system function consists initially of the following subfunctions:
Selftest
Display of emergency call system status
Telephone antenna selection
Voice connection between vehicle and Service Center
Position finding
Data from supplemental restraint system control unit
Manual or automatic emergency call
Information on prioritization of services will be provided at the end of this document.
Further subfunctions are described in separate documents:
Additional telematics services function
Internet connection function
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.
Selftest
If the emergency call system control unit receives the "Terminal 15R" message from the electronic ignition lock control unit, the emergency call system control unit performs a self-test (approx. 8 to 10 s). The light-emitting diodes of the emergency call system button, the MB-Info button and the breakdown assistance button are on for approx. 10 s.
The emergency call system control unit receives the "Terminal 15R" message from the electronic ignition lock control unit via the following route:
Interior CAN
Front SAM control unit with fuse and relay module
Diagnostic CAN
After a successful self-test, the emergency call system is operational and the light-emitting diodes go out.
In the event of a fault, a fault message (depending on the fault type) appears on the instrument cluster, and the LEDs on the emergency call system button, the MB-Info button and the breakdown assistance button are permanently illuminated. Depending on the fault type, the fault is also stored in the emergency call system control unit's fault memory.
Display of emergency call system status
The status of the emergency call system is shown in the following ways:
Display of status through LEDs
Display of status in instrument cluster
Display of status on Audio/COMAND display
With some services, no system-specific status indication takes place in the vehicle.
Display of status through LEDs
The LEDs for the emergency call system button, the MB-Info button and the breakdown assistance button are used to display the following status:
Emergency call system self-test, LEDs light up for approx. 5 s
Active service, each LED flashes on and off
Fault in emergency call system, LEDs permanently on
System readiness of emergency call system, LEDs are off
The emergency call system control unit controls the LEDs in the emergency system button, the MB info button and the breakdown assistance button via direct lines.
Display of status in instrument cluster
The status of the emergency call system is indicated in a text message in the instrument cluster in the following instances:
Active service
Fault in emergency call system
The emergency call system control unit transmits the message to the instrument cluster via the following route:
Diagnostic CAN
Front SAM control unit with fuse and relay module
Interior CAN
Display of status on Audio/COMAND display
An active service of the emergency call system is indicated by a text message or a pop-up (with confirmation prompt) on the Audio/COMAND display.
The emergency call system control unit transmits the text message or the pop-up to the Audio/COMAND display via the following route:
Diagnostic CAN
Front SAM control unit with fuse and relay module
Interior CAN
Audio unit
LVDS line
AMG Performance Media control unit (model 204.0/2/3 with CODE 255 (AMG Performance Media))
LVDS line
Actuation of light-emitting diodes for emergency call system status, illustration of the principle |
A | Emergency call system self-test activated (LEDs on) |
D | Emergency call system self-test finished (LEDs off, if system fault free) |
E | Emergency call system self-test |
N | Active service (LEDs intermittently actuated) |
S | Fault in emergency call system (LEDs permanently on) |
t | Time in seconds (after switching on) |
P82.95-2676-11
Additional function requirements for selecting the telephone antenna
Defect in multifunction antenna or poor reception
Telephone antenna selection
Normally, the communication module integrated into the emergency call system control unit transmits and receives all mobile phone signals via the multifunction antenna. In the event of poor reception or a defective multifunction antenna, 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.
The emergency call system control unit monitors the multifunction antenna via a direct line, and detects the failure or poor reception. The emergency call system control unit then automatically transmits or receives the mobile phone signals for each vehicle-related service via a direct line and the emergency call system antenna.
Additional function requirements for voice connection between vehicle and Service Center
One of the following vehicle-related services is triggered: Manual or automatic emergency call, MB-Info call, breakdown assistance or tracking
Voice connection between vehicle and Service Center
Regardless of the type of vehicle-related service initiated (e.g. MB-Info call), a voice connection is established to the Service Center. Following feedback from the Service Center via a special tone, a Short Message Service (SMS) message is transmitted to the Service Center. This message contains the vehicle position, customer and vehicle identification data and other vehicle data ("Initial Summary"). Then the driver can speak to a service receptionist via the existing voice connection.
The hands-free system microphone is used for voice commands; it is integrated into the inside rear view mirror (A67). The signals of the hands-free system microphone are forwarded via a direct line to the audio equipment. The audio unit then loops through the signals from the hands-free system microphone and forwards them to the communication module integrated into the emergency call system control unit. The communication module integrated into the emergency call system control unit then transmits the hands-free system microphone signals to the Service Center.
The communication module of the emergency call system control unit transmits and receives the mobile phone signals via the following route:
Direct line
Multifunction antenna
In the event of a malfunction in the multifunction antenna (e.g. defective because of a rollover), 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.
The buildup of a voice connection to the Service Center is terminated by the communication module integrated into the emergency call system control unit after several unsuccessful dialing attempts and a corresponding message is shown in the instrument cluster as well as on the Audio/COMAND display. The center instrument panel speaker is actuated by the emergency call system control unit for voice output. For all other applications (e.g. audio mode), the speaker system is muted by a mute signal from the emergency call system control unit over a direct line to the sound system amplifier control unit (with CODE 810 (Sound system)) or to the audio equipment (except CODE 810 (Sound system)). Normally, the voice connection is terminated by the Service Center or by the driver.
If there is an emergency call, the voice connection can only be terminated by the service center or by pressing the accept/terminate phone call button (S111s3) in the "Hang up" subfield for at least 15 s.
Position finding
The emergency call system control unit uses the satellite-supported global positioning system (GPS) to find its location. GPS is available worldwide. GPS position finding is irretrievable after vehicle transport (e.g. by train or ferry or after towing). Relocating with GPS (after interruption of satellite reception) may require several minutes (up to 20 min. when emergency call system control unit is commissioned). Basic position finding runs parallel to GPS position finding.
The position finding function consists of the following component functions:
GPS position finding
Basic position finding
Additional function requirement for GPS position finding
Circuit 15R ON or activation of an authorized service
GPS position finding
The GPS receiver integrated in the emergency call system control unit receives the GPS signals either from the multifunction antenna, or in vehicles with CODE 512 (COMAND APS with DVD changer), or with CODE 527 (COMAND APS with single DVD drive (with navigation)), CODE 508 (Navigation box preinstallation) or CODE 509 (Navigation box) via the Global Positioning System antenna splitter. The GPS signals are used by the emergency call control unit to calculate the current vehicle position (receiver). The vehicle's direction of travel is also determined using the sequence of GPS calculated locations.
Additional function requirement for basic position finding
Circuit 15R ON
Basic position finding
For basic position finding, the emergency call system control unit requires wheel speed and yaw rate signals from the Electronic Stability Program control unit. The Electronic Stability Program control unit sends the signals to the emergency call system control unit via the following route:
Chassis CAN
Front SAM control unit with fuse and relay module
Diagnostic CAN
The emergency call system control unit uses the data to calculate the current vehicle position (longitude and latitude).
Location errors in position finding, rolling backwards with "circuit 15 OFF" (ignition switched off) or transport of the vehicle falsify the basic position finding. In both instances, the deviation is automatically corrected by the navigation processor integrated into the emergency call system control unit when it receives GPS data.
Additional function requirements for data from supplemental restraint system control unit
Circuit 15R ON
Data from supplemental restraint system control unit
In the event of an accident with airbag deployment, an automatic emergency call (E-Call) is made immediately. An emergency call is sent out regardless of the severity of the accident.
The emergency call system control unit receives the crash information via a direct line as a digital crash signal from the supplemental restraint system control unit.
The emergency call system control unit also (redundantly) receives the crash information, including crash level, via the following route:
Chassis CAN
Front SAM control unit with fuse and relay module
Diagnostic CAN
The supplemental restraint system control unit sends a "LIFE" signal (from supplemental restraint system control unit) every t = 500 ms via the same route as the crash information incl. crash level. This allows the emergency call system control unit to permanently monitor communication with the supplementary restraint system control unit and proper function of the crash recognition.
Manual or automatic emergency call
In the event that a driver is confronted with an emergency situation while in a remote location, a Service Center employee can obtain an overview of the situation inside the vehicle with the aid of the data received from the emergency call system control unit (voice connection and SMS) and initiate the appropriate action required for help. An emergency call be initiated manually or automatically. These emergency calls are made for the following reasons:
Automatic alerting of the rescue services after an accident
Alerting of rescue workers at the press of a button (own emergency situation, observed accident)
Reduction in rescue times through fast emergency notification with details on exact location involved
With a manual or an automatic emergency call, the Service Center can transfer the map data to the vehicle if required. The data is made available to the navigation module of the COMAND controller unit (with CODE 512 (COMAND APS with DVD changer) or with CODE 527 (COMAND APS with single DVD drive (with navigation))).
The emergency call function consists of the following subfunctions:
Triggering of a manual emergency call
Triggering of an automatic emergency call
Transmission of the emergency call data and communication with the Service Center
Additional function requirements for triggering a manual emergency call
A higher-priority vehicle-related service (automatic emergency call) is not active
Triggering of a manual emergency call
The manual emergency call is triggered by pressing the emergency call system button marked "SOS". The emergency call system button is covered up with a locking flap. Pressing the protective lid unlocks the lid, and it automatically opens with the aid of a spring mechanism.
The emergency call system control unit reads in the emergency call system button signals via a direct line.
Triggering of an automatic emergency call
The emergency call system control unit receives a crash signal from the supplemental restraint system control unit via a direct line.
Simultaneously, the emergency call system control unit receives the crash signal (redundant) and the crash level from the supplemental restraint system control unit via the following route:
Chassis CAN
Front SAM control unit with fuse and relay module
Diagnostic CAN
Transmission of the emergency call data and communication with the Service Center
After a manual or automatic emergency call has been initiated, the emergency call system control unit establishes a voice connection to the Service Center. After the Service Center replies with a special tone, the emergency call system control unit automatically transmits an SMS with the following data to the Service Center via the integrated communication module:
Vehicle position, direction of travel and history
Vehicle data and crash information
The communication module integrated into the emergency call system control unit transmits and receives the mobile phone signals via the following route:
Direct line
Multifunction antenna
In the event of a manual or automatic emergency call, other vehicle-related services (e.g. MB Info call) are interrupted.
Prioritization
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 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
Electrical function diagram for status display of emergency call system, function | |||
Electrical function diagram for manual or automatic emergency call, function | |||
Electrical function diagram for voice connection between vehicle and Service Center, function | |||
Electrical function diagram for position finding, function | |||
Additional telematics services function | |||
Overview of system components, telematics |