Part 1

GF82.95-P-0004FQU Emergency Call System, Function
MODEL 218
- with CODE (359) TELEAID emergency call system

Function requirements, general
^ Circuit 30 ON
^ No undervoltage or overvoltage
^ The Telematic Alarm Identification on Demand (emergency call system) (TELE AID) is authorized and operating properly
^ Each vehicle-related service is authorized separately
^ An emergency call system control unit (N123/4) communication module authorized for the corresponding vehicle-related service is configured ex-factory with the telephone number of the corresponding service provider
^ The vehicle owner is registered and authorized at an external service provider ("Hughes Telematics Inc.")
^ One mobile phone network is available in sufficient strength and quality

Emergency call system, general
The TELEAID emergency call system was primarily developed to quickly and effectively provide help to the vehicle occupants if an accident occurs or in other emergency situations. For this purpose, the TELE AID emergency call system automatically makes an emergency call (E-call) to the service center of the external service provider if an accident occurs. Accident-relevant data such as the vehicle position and the type of accident are transmitted. The service center will then notify the rescue service, who can initiate the appropriate rescue measures with the help of this information.
Should no connection be established to the service center upon triggering the automatic emergency call, the vehicle occupants are visually instructed via the Audio/COMAND display (A40/8) to call the emergency number "911".
This provides the vehicle occupants with direct contact to the rescue service.
This function is supplemented by further functions:
- Manual emergency call
- Antitheft alarm
- Vehicle tracking
- Vehicle remote unlocking
- Vehicle remote locking
- Roadside assistance
- MB information call
- Manual emergency call:
In the event of robbery or in similar emergency situations, the vehicle occupants can also trigger an emergency call manually.
- Antitheft alarm:
When the antitheft alarm is activated, the vehicle owner is notified of the act via mobile phone. The vehicle owner must now check the situation and possibly make a report to the police, who then issue a registration code for the damage report.
- Tracking the vehicle:
The vehicle function is used to find the vehicle after it was stolen.
After the driver has provided legitimization to the service center via telephone by providing the registration code, the service center transmits the Global Positioning System (GPS) coordinates of the vehicle to the police for tracking purposes.
- Remote door unlocking:
The remote unlocking function enables the vehicle to be remotely unlocked in the event, for example, that a transmitter key (A8/1) is locked in the vehicle and a second transmitter key is not present.
- Remote door locking:
The remote door lock function of the vehicle enables the vehicle owner to remotely lock the vehicle in the event that he/she forgot to lock the vehicle. This service also requires that the vehicle owner provides legitimization to the service center.
- Breakdown assistance:
The breakdown assistance (roadside assistance) function gives the vehicle owner the opportunity to make contact with the Customer Assistance Center (CAC) (e.g. in the event of a defect on the vehicle). The service receptionist of the CAC can now initiate appropriate effective remedial measures, taking into account additional vehicle-specific identifying data.
- MB-Info call:
The MB-Info call function enables the driver to call up information on Mercedes-Benz brand products as well as further voice-based services (e.g. hotel booking) at any time. The following topics can be called up for instance:
- Current traffic conditions
- Technical questions, complaints and services
- Mercedes-Benz products and Mercedes Card
- Leasing and financing offers
All listed vehicle-related services run automatically in the emergency call system control unit. The emergency call system control unit has a priority management feature to ensure that it does not have to manage several vehicle-related services at the same time. This determines the point at which a vehicle-related service is to be activated and which vehicle-related service has the higher priority.
Priority Service
1 Automatic emergency call
2 Manual emergency call
3 Vehicle tracking
4 Roadside assistance
5 MB information call
6 Authorization
7 Vehicle remote unlocking
8 Vehicle remote locking
The emergency call system function consists of the following subfunctions:
^ Function sequence for system start of emergency call system
^ Function sequence for voice connection between vehicle and service center
^ Position finding function sequence
^ Vehicle tracking function sequence
^ Function sequence for manual or automatic emergency call
^ Breakdown assistance function sequence
^ MB-Info function sequence
^ Function sequence for remote door unlocking
^ Vehicle remote locking function sequence

Function sequence for system start of emergency call system
The system start subfunction for the emergency call system is comprised of the following subfunctions:
^ Function sequence for emergency call system self-test
^ Telephone antenna selection function sequence

Function sequence for emergency call system self-test
With circuit 15R On, both red light-emitting diodes (LEDs) integrated into the emergency call system button (S93/3) light up for t = 3.5 s during the self-test of the emergency call system control unit.
The circuit 15R status is sent by the electronic ignition lock control unit (N73) over the interior CAN (CAN B) to the front SAM control unit with fuse and relay module (N10/1) and over diagnostic CAN (CAN D) to the emergency call system control unit.
Actuation is accomplished by the emergency call system control unit via a discrete line. This signals the self-test and activates the check of the following emergency call system states:
- Power supply of emergency call system control unit
- Functions within the emergency call system control unit (e.g. integrated communication module or memory)
- Authorization of emergency call system by the service center
- Communication with the supplemental restraint system control unit (N2/10) and the Electronic Stability Program control unit (N30/4) (without code (233) DISTRONIC PLUS, without model 218.374) or the Electronic Stability Program Premium control unit (N30/7) (with code (233) DISTRONIC PLUS, or model 218.374)
- Emergency call system button function
- Emergency call system antenna (A2/52) (with code (512) COMAND APS with DVD changer)
- Global Positioning System antenna splitter (A2/5) (with code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation))
- Multifunction antenna (A28/11)
Communication between the emergency call system control unit, supplemental restraint system control unit and Electronic Stability Program control unit is checked every t = 500 ms via the following route:
- Chassis CAN (CAN E)
- Front SAM control unit
- Diagnostic CAN
If no fault is present, the two red LEDs integrated into the emergency call system button go out after t = 4 s and thereby signal operational readiness of the emergency call system. If a fault is present of if there is no authorization, a corresponding fault message is output in the multifunction display (A1p13).
Additionally, the two red LEDs in the emergency call system button in the overhead control panel control unit (N70) are permanently actuated.
The message is shown in the multifunction display by the emergency call system control unit via the following route:
- Diagnostic CAN
- Front SAM control unit
- Interior CAN
- Instrument cluster
If an emergency call is triggered or a vehicle-related service is activated, the LED in the emergency call system button, the MB-Info button (S93/6s1) or the breakdown assistance button (S93/6s2) is actuated intermittently.

Function sequence for selection of telephone antenna
The multifunction antenna is monitored with an electric test circuit.
The electric circuit is supplied with electric voltage by the emergency call system control unit. In the event of a voltage drop (e.g. defect due to an accident), the emergency call system control unit recognizes the failure of the multifunction antenna and automatically switches over to the emergency call system antenna.

Function sequence for voice connection between vehicle and service center
A voice connection is established by the emergency call system control unit when the following buttons are pressed:
- Emergency call system button
- MB-Info button
- Breakdown assistance button
The voice input takes place via the handsfree system microphone (A67b1), which is integrated into the inside rearview mirror (A67). The signals from the handsfree system microphone are routed over a direct line to the COMAND controller unit (A40/3). Using the COMAND controller unit, the signals from the handsfree system microphone are routed via a direct line to the communication module integrated into the emergency call system control unit. The communication module then transmits the signals of the handsfree system microphone to the service center.
The communication module transmits and receives the mobile phone signals via the following route:
- Direct line
- Multifunction antenna
Voice output takes place exclusively via the center dashboard speaker (H4/27). It is actuated directly by the emergency call system control unit. At the same time, the emergency call system control unit sends a mute signal via direct line to the COMAND controller unit. Its speaker outputs are then muted. In vehicles with code (810) Sound system, the mute signal is sent via direct line to the sound system amplifier control unit (N40/3). The speaker outputs on the sound system amplifier control unit are muted.
The establishment of a voice connection to the Service Center is interrupted by the communication module integrated into the emergency call system control unit after several unsuccessful dialing attempts. A visual fault message is shown on the Audio/COMAND display.

Additional function requirements for position finding
^ No fault in GPS antenna systems and signals from at least 3 GPS satellites
^ A higher-priority vehicle-related service is not active

Position finding function sequence
The position finding partial function is comprised of the following subfunctions:
^ Function sequence for GPS position finding
^ Function sequence for basic position finding

Function sequence for GPS position finding
The GPS receiver integrated into the emergency call system control unit receives the GPS signals from the multifunction antenna via the following route:
- Direct line
- Global Positioning System antenna splitter (with code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation))
- Direct line
The emergency call system control unit calculates the current position of the vehicle from the GPS signals. The emergency call system control unit stores the last 20 GPS coordinates and updates them permanently.

Basic position finding function sequence
For basic position finding, the emergency call control unit requires the following information:
- Wheel speed signals
- Distance traveled data
- Direction of travel data (forwards or backwards)
The wheel speed signals are recorded by the following components:
- Left front axle rpm sensor (L6/1)
- Right front axle rpm sensor (L6/2)
The wheel speed signals from the rpm sensors are transmitted to the emergency call system control unit via the following route:
- Direct line
- Electronic Stability Program control unit
- Chassis CAN
- Front SAM control unit
- Diagnostic CAN
The instrument cluster (A1) sends the distance traveled data to the emergency call system control unit via the following route:
- Interior CAN
- Front SAM control unit with fuse and relay module
- Diagnostic CAN
The emergency call system control unit receives the data on the direction of travel (forwards or backwards) from the front SAM control unit via diagnostic CAN. After this the emergency call system control unit uses the distance traveled, the vehicle alignment and the direction of travel to calculate the vehicle position (degree of longitude and degree of latitude) at any given time.

Vehicle tracking function sequence
The vehicle tracking partial function consists of the two following subfunctions:
^ "Theft alarm" function sequence
^ "Tracking" function sequence

Additional function requirements for "Theft alarm"
^ Antitheft alarm system (ATA [EDW]) active (t > 30 s)
^ A higher-priority vehicle-related service is not active

"Theft alarm" function sequence
If the ATA [EDW] is triggered, the emergency call system control unit receives an "ATA [EDW] alarm" message in the following way:
- Rear SAM control unit with fuse and relay module (N10/2)
- Interior CAN
- Front SAM control unit
- Diagnostic CAN
The "ATA [EDW] alarm" message is sent by the communication module integrated into the emergency call system control unit to the external service provider via the following route:
- Direct line
- Multifunction antenna
The service center receives the "ATA [EDW] alarm" message and advises the vehicle owner by telephone that the ATA [EDW] alarm has been triggered. "Tracking" will not yet be accomplished by the service center. Once the vehicle owner has been notified by the service center of the triggered ATA [EDW] alarm of his/her vehicle or if the vehicle owner has noticed the theft of the vehicle, the vehicle owner must report the theft to the police. The vehicle owner then receives a number from the police that confirms that the vehicle theft has been reported. With this number, the vehicle owner calls the service center and gives the number to a service receptionist.
The service center checks the query and the legitimacy of the vehicle owner and then initiates the "Tracking" procedure.