Emergency Call System, Function - GF82.95-P-0004FG
Model 213
up to model year 2021
with code 351 (eCall emergency call system)
Shown on model 213 as of 01.06.2018
Shown on model 213 up to 31.05.2018
Model 213
up to model year 2021
with code 351 (eCall emergency call system)
with code 446 (Touchpad only)
Model 213
up to model year 2021
with code 351 (eCall emergency call system)
with code 448 (Touchpad)
Information on touchpad
The touchpad is installed in two variants.
Variant (with code 448 (Touchpad)): The touchpad is installed together with the Audio/COMMAND control panel. The touchpad is connected only to the telematics CAN.
Variant 2 (with code 446 (Touchpad only)): The touchpad is installed instead of the Audio/COMMAND control panel. n this case, the upper control panel control unit (N72/1), the left lower control panel and the right lower control panel are connected through the LCP-LIN to the touchpad. The touchpad is also connected to the telematics CAN.
Function requirements, general
- Circuit 30 ON
- Transport mode not active
- The communications module of the HERMES control unit is configured with the telephone number of the relevant service provider.
Emergency call system, general
The emergency call system allows a manual or automatic emergency call to be triggered. The emergency call is received by the MercedesBenz Service Center. The user is spoken to in the language that is selected in the system settings of the head unit. If necessary, the Mercedes-Benz Service Center notifies the local rescue services. If the Mercedes-Benz Service Center is not staffed, the emergency call is automatically forwarded to the local rescue services 112.
If the HERMES control unit receives the message "Circuit 15" from the electronic ignition lock control unit over the diagnostic CAN, it checks the operational readiness of the emergency call system. After a successful check, the emergency call system is operational and "SOS ready" appears on the Audio/COMMAND display. The following checks are carried out:
- Receipt of cyclic readiness signal ("sign of life") from the Supplemental Restraint System control unit
- Connection for muting audio sources
- Connection to the driver hands-free system microphone, from the head unit
Emergency call system status indication
The status of the emergency call system is shown in the following ways:
- Status indication on the Audio/COMMAND display
- Status indication via light-emitting diode
- Status indication in instrument cluster
Status indication on the Audio/COMMAND display
The status of the emergency call system is indicated by a text message on the Audio/COMMAND display in the following cases:
- Emergency call system operational or not operational ("SOS ready" or "SOS not ready" in telephone menu)
- Emergency call has been activated ("activating" (call setup), "transmitting data" (data telegram transmission), "connected" (voice connection established))
- Emergency call forwarded to local 112 rescue services (the address (with code 531 (COMMAND APS)) and the coordinates of the vehicle position are also shown)
- Call activation has failed several times ("MB emergency call processing failed. Please dial 112 on the mobile phone.")
If an emergency call is active, the top right of the Audio/COMMAND display also shows a telephone symbol, an emergency call symbol and the field strength of the HERMES control unit.
Position finding
On vehicles with code 355 (Preinstallation for navigation retrofit) or with code 531 (COMMAND APS), the HERMES control unit takes over the signals of the position finding from the head unit. The head unit transmits the position finding signals to the HERMES control unit via the user interface CAN, electronic ignition lock control unit and diagnostic CAN.
As of 01.06.2019, the HERMES control unit also performs its own position finding. As a result, the HERMES control unit can immediately compensate for a lack of signals from the head unit.
Position finding is carried out by the HERMES control unit on vehicles except code 355 (Preinstallation for navigation retrofit) and except code 531 (COMMAND APS).
For position finding, the HERMES control unit uses the global navigation system (GPS). GPS is available worldwide. GPS position finding is irretrievable after vehicle transport (e.g. by train or ferry or after towing). Recalculation of the GPS position (following an interruption in satellite reception) can take several minutes. At the same time as the GPS position finding the HERMES control unit conducts a permanent basic position finding, that enables the position of the vehicle to be determined even when the GPS reception fails.
The position finding function consists of the following component functions:
- Emergency call system antenna 1
- Emergency call system antenna 2 (with code 362 (HERMES LTE))
- Connection to GPS antenna
In the event of a fault, depending on the fault type, a fault message appears on the Audio/COMMAND display and the fault is stored in the fault memory of the HERMES control unit. If, after switching off the ignition, the Supplemental Restraint System control unit switches to the "Sleep" mode, it no longer sends a readiness signal and the "SOS NOT READY" message is shown.
The electronic ignition lock control unit transmits circuit status "circuit 15" to the HERMES control unit via the diagnostic CAN.
The emergency call system function includes the following subfunctions:
- Emergency call system status indication
- Position finding
- Manual or automatic emergency call
The HERMES control unit transmits the display information to the head unit via the diagnostic CAN, electronic ignition lock control unit and user interface CAN.
The head unit transmits a switch-on request to the Audio/COMMAND display via the telematics CAN, prepares the visualization, and transmits the picture data to the Audio/COMMAND display via the HSVL line.
Some text messages on the Audio/COMMAND display can be confirmed with the Audio/COMMAND control panel (except code 446 (Touchpad only)) or the touchpad (with code 446 (Touchpad only) or code 448 (Touchpad)). The Audio/COMMAND control panel or the touchpad transmits the signals to the HERMES control unit via the telematics CAN, head unit, user interface CAN, electronic ignition lock control unit and diagnostics CAN.
Status indication via light-emitting diode
The SOS button LED is used to indicate the following statuses:
- Active service, light-emitting diode flashes
- Emergency call system self-diagnosis, light-emitting diodes light up for approx. 5 s
- Fault in emergency call system, LEDs permanently on
- Diagnosis
The HERMES control unit transmits the request to switch on the LED to the overhead control panel control unit via the diagnostic CAN, electronic ignition lock control unit and interior CAN. The overhead control panel control unit controls the LED in the SOS button.
Status indication in instrument cluster
If the HERMES control unit fails, the message "SOS nonfunctional" is displayed in the instrument cluster. The HERMES control unit continuously transmits the system status to the instrument cluster via the diagnostic CAN, electronic ignition lock control unit and user interface CAN.
- GPS position finding
- Basic position finding
GPS position finding
On vehicles with code 355 (Pre-installation for navigation retrofit) or with code 531 (COMMAND APS), the head unit receives the GPS signals from the GPS antenna.
On vehicles except code 355 (Pre-installation for navigation retrofit) and except code 531 (COMMAND APS), the HERMES control unit receives the GPS signals from the GPS antenna.
Additional function requirement for basic position finding
- Terminal 15 ON
Basic position finding
The HERMES control unit requires the following signals for basic position finding:
- Wheel speed and yaw rate signals from the Electronic Stability Program control unit
- Steering wheel angle sensor signal
The Electronic Stability Program control unit transmits the wheel speed and yaw rate signals to the HERMES control unit via the chassis FlexRay, electronic ignition lock control unit and diagnostic CAN.
The steering column tube module control unit transmits the signals from the steering wheel angle sensor to the HERMES control unit via the chassis FlexRay, electronic ignition lock control unit and diagnostic CAN.
The HERMES control unit uses the data to calculate the instantaneous position of the vehicle (longitude, latitude and direction of travel).
Rolling backwards with "Circuit 15 OFF" (ignition switched off) or transport of the vehicle falsify the basic position finding. In both cases, this deviation is automatically corrected on receipt of GPS data.
Manual or automatic emergency call
In an emergency situation, a service receptionist from the MercedesBenz Service Center can obtain an overview of the condition inside the vehicle with the aid of the data received from the HERMES control unit (voice connection and data telegram) and initiate appropriate help measures. 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 rescue services by pushing a button (own emergency situation, observed accident)
- Reduction in rescue times through fast emergency notification with details on exact location involved
The automatic emergency call has priority over a manually triggered emergency call. If an automatic emergency call is triggered during a manual emergency call, the manual emergency call is interrupted. If a manual emergency call is triggered during an automatic emergency call, it is ignored. However, a data telegram containing updated position data is sent to the Mercedes-Benz Service Center, and the existing connection is maintained.
The manual or automatic emergency call function consists of the following subfunctions:
- Triggering of an automatic emergency call
- Triggering of a manual emergency call
- Voice connection between vehicle and Service Center
Additional function requirements for triggering an automatic emergency call
- Terminal 15 ON
Triggering of an automatic emergency call
In the event of an accident with deployment of the restraint systems (not the PRE-SAFE® system) an automatic emergency call (E-call) is immediately sent. An emergency call is sent out regardless of the severity of the accident.
The HERMES control unit receives the crash information via the seat occupancy LIN as a digital crash signal from the supplemental restraint system control unit.
In addition (and redundantly), the Supplemental Restraint System control unit transmits the crash information - including the crash level - to the HERMES control unit via the user interface CAN, electronic ignition lock control unit and diagnostic CAN.
The Supplemental Restraint System control unit transmits a readiness signal cyclically via the same route (e.g. every 500 ms). This enables the HERMES control unit to monitor communication with the supplemental restraint system control unit and correct operation of the crash detection.
If the Active Emergency Stop Assist (with code 23P (Driving Assistance Package) or code P20 (Driving Assistance Plus Package)) brakes the vehicle to a standstill, the Mercedes-Benz Intelligent Drive control unit sends the request for an automatic emergency call over the suspension FlexRay, electronic ignition lock control unit and the diagnostics CAN to the HERMES control unit.
Additional function requirements for triggering a manual emergency call
- No automatic emergency call is active.
Triggering of a manual emergency call
The manual emergency call is triggered by pressing the SOS button. 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 overhead control panel control unit sends the status of the SOS button over the interior CAN, electronic ignition lock control unit and the diagnostic CAN to the HERMES control unit.
Voice connection between vehicle and Service Center
Once the emergency call has been triggered, the HERMES control unit sets up a voice connection with the Mercedes-Benz Service Center via emergency call system antenna 1 or emergency call system antenna 2 (with code 362 (HERMES LTE)).
Model 213
up to model year 2021
with code 351 (eCall emergency call system)
with code 362 (HERMES communications module LTE)
Emergency call system antenna 1 and emergency call system antenna 2 are used to set up the connection in order to form transmission and reception diversity.
The status of the connection setup is indicated by the following messages on the Audio/COMMAND display:
- "Activating" (setting up the call)
- "Transmitting data" (transmission of emergency call data (data telegram))
- "Connected" (voice connection established)
Establishing a voice connection to the Mercedes-Benz Service Center is canceled after several failed attempts to connect, and the following message is shown on the Audio/COMMAND display: "MB emergency call activation failed. Please dial 112 on the mobile phone." To prevent the automatic emergency call from being terminated unintentionally on vehicles as of 01.06.2018, the accept/terminate phone call switch on the head unit multifunction steering wheel button group is temporarily disabled while the connection is being established.
Model 213
up to model year 2019
with code 351 (eCall emergency call system)
To avoid any unintentional termination of the automatic emergency call, the Accept/Terminate phone call button (S163/2s3) on the multifunction steering wheel is temporarily disabled while the connection is being established.
While the connection is being set up, audio sources are muted (mute function) and existing telephone connections are interrupted. In vehicles except AMG as of 01.06.2018, except code 810 (Sound system) and except code 811 (Advanced sound system), the HERMES control unit sends the signal for the mute function to the head unit.
In AMG vehicles except code 810 (Sound system) and except code 811 (Advanced sound system) as of 01.06.2018, the HERMES control unit transmits the signal for the mute function to the Midline sound system amplifier control unit.
In vehicles with code 810 (Sound system), the HERMES control unit sends the signal for the mute function to the sound system amplifier control unit.
In vehicles with code 811 (Advanced sound system), the HERMES control unit sends the signal for the mute function to the Advanced sound system amplifier control unit.
As soon as a connection is set up to the Mercedes-Benz Service Center, the HERMES control unit automatically sends a data telegram to the Service Center. The data telegram transmits the following data:
- Time stamp
- GPS position of vehicle
- Language
- Vehicle identification number
- MB Contact status (ON or OFF)
- Position history (Tracing of vehicle positions up to a distance of a few 100 m from current location)
- Number of vehicle occupants (estimated)
After a data telegram has been transmitted to the Mercedes-Benz Service Center, the user can speak to a service receptionist via the voice connection. The Mercedes-Benz Service Center carries out the call in the language that was selected in the system settings of the head unit and transmitted in the data telegram, where possible. The driver hands-free system microphone, which is installed on the driver side of the roof interior trim, is used for the voice input. The hands-free system is not available for telephone calls throughout the duration of the emergency call.
The HERMES control unit receives the outgoing voice signals from the driver hands-free system microphone via the head unit.
The HERMES control unit outputs the incoming voice signals over the center instrument panel speaker (except code 811 (Advanced sound system)) or over the center instrument panel midrange speaker (with code 811 (Advanced sound system)).
The volume of the voice output can be adjusted using the following controls:
- Head unit multifunction steering wheel button group (as of 01.06.2018)
The steering wheel electronics read in the operation signals from the volume adjustment switch directly. The steering column tube module control unit reads them in over the steering wheel CAN and sends them over the suspension FlexRay, electronic ignition lock control unit and the user interface CAN to the instrument cluster. The instrument cluster transmits the control signals from the multifunction steering wheel button groups to the control unit via the user interface CAN, electronic ignition lock control unit and diagnostic CAN.
- Instrument cluster multifunction steering wheel button group (up to 31.05.2018)
The steering wheel electronics reads the control signals directly. The steering column tube module control unit reads them via the steering LIN and transmits them to the instrument cluster via chassis FlexRay, the electronic ignition lock control unit and user interface CAN. The instrument cluster transmits the control signals from the multifunction steering wheel button groups to the control unit via the user interface CAN, electronic ignition lock control unit and diagnostic CAN.
- Volume adjustment button in the lower control panel
The respective lower control panel transmits the operation signals to the head unit via the LCP-LIN, Audio/COMMAND control panel (except code 446 (Touchpad only)) or touchpad (with code 446 (Touchpad only)) and telematics CAN. The head unit transmits the control signals to the HERMES control unit via the user interface CAN, electronic ignition lock control unit and diagnostic CAN.
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 head unit.
| Electrical function diagram for manual or automatic emergency call function | PE82.95-P-2066-97DBA | ||
| Overview of system components, telematics | GF82.85-P-9999FG |