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Mobile phone system, function - GF82.70-P-0007RF

Model 205, 253 

Fig 1: Mobile Phone System - Function Diagram (Shown On Model 205, 253)
G10134505Courtesy of MERCEDES-BENZ USA

Shown on model 205, 253 

Function requirements for mobile phone system, general 

IMPORTANT Additional information available at:

Mobile telephone system, general 

A differentiation is made between the following equipment and utilization variants in the mobile phone system:

All variants use Bluetooth® for data transfer.

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile))

Telephony via the telephone module with Bluetooth® (SAP profile) requires equipment with CODE 386 (Comfort telephony). Instead of the mobile phone cradle (accessories), the telephone module with Bluetooth® (SAP profile) can be plugged into the mobile phone contact plate.

IMPORTANT A mobile phone authorized on the audio equipment can be used as a playback device as part of Bluetooth® audio.

IMPORTANT Model 205

except code 348 (Emergency call/assistant system)

A mobile phone authorized on the head unit can also be used as a modem to access the Internet.

The head unit sends and receives telephone signals over the Bluetooth® antenna. The head unit generates the displays and transmits them to the Audio/COMAND display via an LVDS line. If the head unit is not switched on, it can be activated via the "ON" button in the left lower control panel (with manual transmission) or in the right lower control panel (with automatic transmission).

The signal of the "ON" button is forwarded by the left lower control panel (with manual transmission) or by the right lower control panel (with automatic transmission) as follows:

LCP LIN →

Audio/COMAND control panel →

Telematics CAN →

Head unit

IMPORTANT The mobile phone system is described here using basic telephony as an example. The special comfort telephony features are summarized at the end of this information.

The mobile phone system includes the following areas:

Bluetooth® 

Using Bluetooth®, it is possible to quickly and easily connect mobile terminals that support the corresponding profiles to the mobile phone system. Bluetooth® is a worldwide open standard for connecting Bluetooth® devices (e.g. mobile phone) wirelessly and is based on radio technology in the 2.4 GHz range. One advantage of Bluetooth®, in addition to the wide availability of Bluetooth® devices, is the uncomplicated and spontaneous connection of Bluetooth® devices. The extremely high data security (128-bit encoding) and the relatively limited radius (approx. 10 m) of this type of Bluetooth® network are what makes the use of Bluetooth® in the vehicle interesting. The head unit can integrate mobile phones into the vehicle hierarchy over the mobile phone's Bluetooth® interface and the Bluetooth® antenna. The head unit automatically searches for the last two connected mobile phones and connects to the mobile phone that responds first.

IMPORTANT If the mobile phone is not automatically connected to the head unit or if the head unit is to be establish a connection to another mobile phone, then the connection must be made manually over the telephone base function. Authorized telephones can be selected from a list. Non-authorized telephones must be authorized first. Up to 15 mobile phones can be authorized at the same time. When authorizing a new telephone if 15 telephones are already authorized, the user is prompted to first delete one of the existing data records. Detailed information on authorization is available in the respective operator's manual.

Switch on/off characteristics 

A mobile phone operated via Bluetooth® is switched on and off on the mobile phone itself. The SIM PIN prompt, if configured on the mobile phone and it is transmitting the status, occurs on the mobile phone only and the PIN must be entered on the mobile phone itself. Following connection to the mobile telephone network of the mobile telephone network provider, the provider and the strength of the signal are displayed in the status bar of the Audio/COMAND display.

The switch-off signal via the mobile phone button is processed internally in the mobile phone. If the rechargeable battery of the mobile phone is empty, the mobile phone is also switched off. This process also runs internally in the mobile phone. The message "Ready for Bluetooth® telephony" is displayed on the Audio/COMAND display and the system automatically searches for mobile phones used last. The head unit can be switched on and off with the "ON" button on the left lower control panel (with manual transmission) or on the right lower control panel (with automatic transmission).

The control signal of the "ON" button is sent as follows:

LCP LIN →

Audio/COMAND control panel →

Telematics CAN →

Head unit

Call signal 

The head unit receives the call signal over the Bluetooth® antenna from the mobile phone. The head unit sends the ringing tone via direct lines to the speaker system or, on vehicles with CODE 810 (Sound system), via MOST to the sound system amplifier control unit, which amplifies the signals and transmits them to the speaker system. If the mobile phone supports "In-band ringing", the mobile phone ring tone is emitted over the speakers, otherwise the head unit's default ringing sound is used.

IMPORTANT The head unit mutes the currently active audio source (e.g. during radio mode) and displays the caller ID over the LVDS line on the Audio/COMAND display.

Establish, end, accept, reject or toggle call 

Telephone numbers can be entered using a character bar on the Audio/COMAND display or they can be searched for and selected in call lists or in the address book. The mobile phone system can be operated using the following components:

IMPORTANT Toggle: If during a telephone call another incoming call is received or another telephone connection is set up, then the new call is activated and the existing one put on hold. It is then possible to switch (toggle) between the active call and the one on hold.

IMPORTANT Conference connection: If the mobile phone supports the function, it is possible - after several calls have been connected - to switch, not only between the calls, as for toggling, but to have all the calls active at the same time in a conference connection.

Mobile phone 

The mobile phone control is processed internally, status changes are received by the head unit over the Bluetooth® antenna.

Upper control panel control unit 

The Telephone menu can be called up on the upper control panel control unit.

The control signal is transferred as follows:

LCP LIN →

Audio/COMAND control panel →

Telematics CAN →

Head unit

Audio/COMAND control panel 

The Audio/COMAND controller is used to call up and activate the functions in the Telephone menu. The "Back" button supports navigation in the menus.

The control signals from the Audio/COMAND control panel are forwarded to the head unit via telematics CAN.

Multifunction steering wheel button groups 

The control signals of the multifunction steering wheel button groups are forwarded via the following components:

Steering wheel electronics →

Steering LIN →

Steering column tube module control unit →

Chassis FlexRay →

Electronic ignition lock control unit →

User interface CAN →

Instrument cluster →

User interface CAN →

Head unit

Voice control system (VCS [SBS]) (with CODE 531 (COMAND APS)) 

The voice control system is activated on the left multifunction steering wheel button group. When a call is being connected or a call being accepted, the voice control system is automatically switched off.

The control signal of the left multifunction steering wheel button group is forwarded as follows:

Steering wheel electronics →

Steering LIN →

Steering column tube module control unit →

Chassis FlexRay →

Electronic ignition lock control unit →

User interface CAN →

Instrument cluster →

User interface CAN →

Head unit

When the voice control system is active, the voice commands are recorded by the hands-free system microphone and forwarded via a direct line to the head unit. If necessary, the head unit sends the control signals over the Bluetooth® antenna to the mobile phone.

IMPORTANT Model 205, 253

with code 531 (COMAND APS)

The individual voice commands are listed in the "Linguatronic operator's manual".

Touchpad (up to 31.05.2015 with code 531 (COMAND APS), with code 522 (Audio 20 radio), as of 01.06.2015 with code 448 (Touchpad), with code 498 (Japan version) or code 494 (USA version)) 

The head unit receives the control signals from the touchpad via the telematics CAN.

Using the phone in hands-free mode 

The voice input in the hands-free mode is recorded by the hands-free system microphone, and forwarded to the head unit. The head unit sends the signals over the Bluetooth® antenna to the mobile phone. The head unit receives the incoming signals over the Bluetooth® antenna from the mobile phone and emits them at the speaker system. On vehicles with code 810 (Sound system), the head unit forwards the incoming voice signals along with the audio parameters (e.g. volume) via MOST to the sound system amplifier control unit, which then amplifies the signals and sends them to the speaker system. The volume of the voice outputs can e.g. be adjusted at the head unit, with the right multifunction steering wheel button group, with the volume button (with manual transmission) in the left lower control panel or with the volume button (with automatic transmission) in the right lower control panel.

The control signal of the right multifunction steering wheel button group is forwarded as follows:

Steering wheel electronics →

Steering LIN →

Steering column tube module control unit →

Chassis FlexRay →

Electronic ignition lock control unit →

User interface CAN →

Instrument cluster →

User interface CAN →

Head unit

The control signal of the volume button (with manual transmission) in the left lower control panel or the volume button (with automatic transmission) in the right lower control panel is forwarded as follows:

LCP LIN →

Audio/COMAND control panel →

Telematics CAN →

Head unit

Phone book 

The telephone book contains the telephone entries stored in the head unit. The user can manage (view and delete) his contact data in the telephone book. The system can be provided with the stored information via the phone book entries and the connection established immediately.

IMPORTANT Read access to the phone book of the mobile phone is provided if the mobile phone supports the Bluetooth Phonebook Access Profile (PBAP). Otherwise, data from the phone book of the mobile phone can only be loaded onto the head unit via "vCards".

IMPORTANT Model 205

except code 494 (US version)

except code 498 (Japanese version)

The telephone book has a permanently reserved telephone book entry "Mercedes-Benz Contact" with the Service Center's telephone number. If the telephone number of the Service Center is dialed, the connection is not made through the mobile phone, but over the telematics services communications module (N112/1).

Address book 

The user can manage all the contact data in the address book (view, edit, add, delete and create). The address book contains the address entries stored in the head unit. Address entries can only be removed by deleting individual entries or by deleting the entire address book. Address-relevant mobile phone system applications can be directly started and supplied with the stored data via address book entries. Address data from external devices (such as PDAs, notebooks, etc.) or storage media (e.g. Secure Digital (SD) card, Universal Serial Bus (USB) storage) can be stored in the address book and are then permanently available as address entries. The address data can be sent to the address book via the following system components:

The address data transmitted via Bluetooth® is received by the head unit from the Bluetooth® antenna. Address data from the USB electrical connectors (with code 520 (Audio 20 USB)) or the multimedia connection unit (with code 522 (Audio 20 radio) or code 531 (COMAND APS)) is received by the head unit via a direct line.

Address book entries can contain the following information among other things:

IMPORTANT Model 205

with code 498 (Japanese version)

The call can be established via the voice control system for each entry with a completed "Yomigana field".

Speed-dial list 

The speed dial list consists of up to ten telephone numbers to which phone book entries can be assigned with digits from 0 to 9. The user can manage the entries using the "Call lists" and "Speed dial list" menu entries. The speed dial list is active only when the "Telephone" menu is active.

"Seamless switch" 

"Seamless Switch" provides the following functionality:

IMPORTANT Model 205

with code 498 (Japanese version)

With some Japanese mobile phones you can select how the mobile phone behaves if a connection is interrupted. If the "Switch off if connection is interrupted" setting has been selected, "Seamless Switch" cannot be activated because a brief connection interruption occurs.

Short Message Service (SMS) (except CODE 498 (Japan version)) 

The SMS application enables the user to receive, send or manage his/her SMS messages (e.g. to read or delete them). For this, the SMS messages previously received on the mobile phone as well as the new SMS messages are forwarded to the head unit. The following SMS functions are possible:

IMPORTANT The SMS function with basic telephony requires the Message Access Profile (MAP) to be supported. Under certain circumstances, loading SMS messages may take a long time. This may be because of the mobile phone or the number of SMS messages in the mobile phone.

As soon as the head unit is connected to the mobile phone, it starts to receive the SMS messages already stored in the mobile phone, and any new incoming SMS messages over the mobile phone's Bluetooth® antenna. The functions for writing, sending and managing SMS messages are activated through the basic telephone function. The head unit controller unit displays the SMS messages on the Audio/COMAND display via the LVDS line. When reading the SMS message, the head unit sends the audio signals either straight to the speaker system or, on vehicles with CODE 810 (Sound system), via MOST to the sound system amplifier control unit.

Comfort telephony (with CODE 386 (Comfort telephony)) and telephony with CODE 379 (Telephone module with Bluetooth® (SAP profile)) 

The mobile phone signals are sent and received over the left telephone antenna or right telephone antenna. The connection is made via the telephone antenna splitter, the cellular telephone system antenna amplifier/compensator and the mobile phone contact plate in the stowage compartment (telephone compartment) beneath the armrest. On vehicles with code 386 (Comfort telephony) (except code 379 (Telephone module with Bluetooth® (SAP))), a suitable mobile phone cradle (accessories) is plugged into the mobile phone contact plate and then the respective mobile phone is plugged into the cradle. In vehicles with CODE 379 (Telephone module with Bluetooth® (SAP profile)), the telephone module with Bluetooth® (SAP profile) is connected to the mobile phone contact plate.

IMPORTANT Model 205 as of 6/1/15

as of model year 2016

with code 379 (Telephone module with Bluetooth® (SAP profile))

Model 205 as of 6/1/15

as of model year 2016

with code 386 (Comfort telephony)

Model 253

with code 379 (Telephone module with Bluetooth® (SAP profile))

Model 253

with code 386 (Comfort telephony)

The mobile phone system supports the Long Term Evolution (LTE) mobile radio standard.

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile))

The telephone module with Bluetooth® (SAP profile) supports the SIM Access Profile (SAP).

The comfort telephony and telephony with CODE 379 (Telephone module with Bluetooth® (SAP profile)) exhibit the following features:

Mobile phone contact plate functions 

The mobile phone contact plate fulfills the following functions:

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile))

Model 205, 253

with code 386 (Comfort telephony)

The connection to the head unit (over Bluetooth®) is set up by the mobile phone or the telephone module with Bluetooth® (SAP profile).

signal curve 

The mobile phone signals are received from the mobile telephone network as follows:

Left telephone antenna or right telephone antenna →

Telephone antenna splitter →

Cellular telephone system antenna amplifier/compensator →

Mobile phone contact plate

In vehicles with CODE 386 (Comfort telephony), the mobile phone contact plate routes the mobile phone signals over the mobile phone cradle (accessories) and on to the mobile phone. On vehicles with code 379 (Telephone module with Bluetooth® (SAP)), the Bluetooth® module forwards the mobile phone signals to the telephone module with Bluetooth® (SAP). The mobile phone or the telephone module with Bluetooth® (SAP profile) routes the mobile phone signals over the Bluetooth® antenna to the head unit.

Switch-on characteristics 

The mobile phone system is automatically switched on by a wake-up pulse when the head unit is switched on. The head unit sends the signal over a direct line to the mobile phone contact plate. The mobile phone contact plate forwards the signal with CODE 379 (Telephone module with Bluetooth® (SAP profile)) to the telephone module with Bluetooth® (SAP profile) and with CODE 386 (Comfort telephony) over the cradle to the mobile phone.

Personal Identification Number (PIN) query 

A prompt for the PIN is shown after switching on the mobile phone if the mobile phone is configured for this. The PIN prompt is shown by the head unit over an LVDS line on the audio/COMAND display. The PIN can be entered using the head unit controls. For the telephone module with Bluetooth® (SAP profile) (with CODE 379 (Telephone module with Bluetooth® (SAP profile))), the PIN for a connected telephone or the SIM card can be stored so that it does not have to be entered again when the phone is switched on.

Telephone module with Bluetooth® (SAP profile) (with CODE 379 (Telephone module with Bluetooth® (SAP profile))) 

After this the telephone module with Bluetooth® (SAP profile) is connected to the vehicle.

The telephone module with Bluetooth® (SAP profile) can be used in two different ways to make a call:

Mobile phones that are to be used for telephony with the telephone module with Bluetooth® (SAP profile), must support the SIM Access Profile and be connected once (authorized) to the telephone module with Bluetooth® (SAP profile). Up to 15 mobile phones can be authorized. After switching on the head unit, an automatic search is performed for the last two SAP telephones used in the vehicle, and the first one that responds to the prompt is connected, when the following conditions are given:

If another mobile phone is to be connected, then the connection has to be interrupted first and then the corresponding mobile phone manually connected by selecting it from a list of SAP telephones.

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile))

If necessary the mobile phone can be charged using a USB connection on the telephone module with Bluetooth® (SAP profile). To do this, the cover on the telephone module with Bluetooth® (SAP profile) has to be removed. The USB connector on the telephone module with Bluetooth® (SAP profile) can also be used for installing software updates, e.g. with a USB memory (USB stick). The update files and the procedure are made available to the customer on the Internet.

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile)) The telephone module with Bluetooth® (SAP profile) is Internet capable when the mobile phone contract includes a data option.

IMPORTANT Model 205, 253

with code 379 (Telephone module with Bluetooth® (SAP profile)) A ring tone can be selected for the respective SIM card or SAP telephone from a list of ring tones.

SMS (with CODE 379 (Telephone module with Bluetooth® (SAP profile))) 

State of the art mobile phones come with two memories for SMS messages: one on the telephone and one on the SIM card. As long as the mobile phone is used for telephony with CODE 379 (Telephone module with Bluetooth® (SAP profile)), incoming SMS messages on the mobile phone can only be stored on the SIM card. Storing incoming SMS messages on the SIM card can lead to the following problems:

Electrical function schematic for mobile phone PE82.70-P-2051-97FBA
Overview of system components, telematics GF82.85-P-9999RF 
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