Mobile Phone System In Rear Passenger Compartment, Function - GF82.70-P-0008LF

Model 222 up to model year 2018 with code 855 (Telephony in rear passenger compartment) 

Model 222 up to model year 2018 with code 856 (Business telephony in rear passenger compartment) 

Courtesy of MERCEDES-BENZ USA

Shown on model 222 

Function requirements for mobile phone system in rear, general 

• Circuit 30g ON
• Transport mode not active
• Mobile phone with Bluetooth capability in vehicle and authorized at the Rear Seat Entertainment system controller unit

Mobile phone system in rear 

The mobile phone system in the rear can be used in various ways. A differentiation is made between the following operating modes:

• Basic telephony
• Comfort telephony (with CODE 856 (Business telephony in rear))
• Connection assumed by front mobile phone system
• Connection transferred to front mobile phone system
• Making calls in "handset mode" through rear handset

In basic telephony the mobile phone is connected through the rear Bluetooth® antenna to the Rear Seat Entertainment controller unit.

The cellular telephone system signals are sent by the mobile phone into the mobile telephone network. The mobile phone is not charged.

In comfort telephony (with CODE 856 (Business telephony in rear)), the mobile phone is inserted into the rear mobile phone cradle (accessories). The mobile phone can be connected to either the Rear Seat Entertainment system controller unit or the COMAND controller unit. The mobile phone sends and receives the cellular telephone system signals over the multifunction antenna, and routes the signals over Bluetooth® to either the rear Bluetooth® antenna or the Bluetooth® antenna (depending on whether the mobile phone is connected to the Rear Seat Entertainment system controller unit or to the COMAND controller unit). The switch-on signal (wake-up signal) is always sent by the COMAND controller unit via the Rear Seat Entertainment system controller unit to the rear mobile phone contact plate. The mobile phone is charged through the rear mobile phone contact plate by the Rear Seat Entertainment system controller unit.

Model 222 up to model year 2018 with code 374 (Additional telephone module with Bluetooth® SAP) with code 855 (Telephony in rear passenger compartment)

Model 222 up to model year 2018 with code 379 (Telephone module with Bluetooth® (SAP profile)) with code 855 (Telephony in rear passenger compartment)

Instead of the rear mobile phone cradle, a telephone module with Bluetooth® (SAP) can also be plugged into the rear mobile phone contact plate. The telephone module with Bluetooth® (SAP profile) is charged via the rear mobile phone contact plate.

If the connection from the front mobile phone system is transferred to the rear (or vice versa), then the Rear Seat Entertainment system controller unit and the COMAND controller unit exchange the signals over MOST.

Making calls in the "Handset mode" through the rear handset can also be combined with the previously mentioned variants (Exception: Connection transferred to front mobile phone system). In this case, incoming telephone signals are output over the rear handset and not over the rear speakers. In this case, the outgoing telephone signals are read in through the rear handset, and not by the left rear hands-free system microphone and the right rear hands-free system microphone. It is possible to switch between the "handset mode" and the "handsfree mode" when making a call.

The rear mobile phone system is operated using the rear handset. Operation through the mobile phone connected with the Rear Seat Entertainment system controller unit is also possible.

The rear mobile phone system encompasses the following function sequences:

• Function sequence for basic telephony 
• Function sequence for comfort telephony (with CODE 856 (Business telephony in rear)) 
• Function sequence for connection assumed from front mobile phone system 
• Function sequence for connection transferred to front mobile phone system 
• Function sequence for making calls in "Handset mode" 

This document contains the following additional information:

• "Seamless switch" 
• SMS 
• Speed-dial list 
• Telephone conference and toggling 
• Address book 

Function sequence for basic telephony 

A differentiation is made between the following procedures for basic telephony in the rear:

• Incoming mobile phone signals 
• Outgoing mobile phone signals 

Incoming mobile phone signals 

The mobile phone receives cellular telephone system signals and sends them over Bluetooth® to the rear Bluetooth® antenna, which forwards the signals to the Rear Seat Entertainment system controller unit. The Rear Seat Entertainment system controller unit sends the call signal over MOST to the COMAND controller unit. In vehicles except CODE 810 (Sound system) or CODE 811 (Advanced sound system), the COMAND controller unit outputs the call signal over the rear speakers. In vehicles with CODE 810 (Sound system) or with CODE 811 (Advanced sound system), the sound system amplifier control unit receives the call signal over MOST and outputs it over the rear speakers.

If the call is accepted, the Rear Seat Entertainment system controller unit continues to send the incoming telephone signals for the handsfree system over MOST to the COMAND controller unit or to the sound system amplifier control unit and for the "Handset mode" over the rear Bluetooth® antenna to the rear handset.

The rear handset cradle is only used to store the device and to charge the rear handset.

Outgoing mobile phone signals 

A new telephone connection can be made or an incoming call can be accepted on the mobile phone or the rear handset. In these instances, the signal is forwarded by the rear Bluetooth® antenna to the Rear Seat Entertainment system controller unit.

During hands-free operation the left rear hands-free system microphone and the right rear hands-free system microphone route the outgoing cellular telephone system signals to the Rear Seat Entertainment system controller unit. In the "Handset mode", the rear handset routes the outgoing cellular telephone system signals over the rear Bluetooth® antenna to the Rear Seat Entertainment system controller unit. The Rear Seat Entertainment system controller unit sends the outgoing telephone signals over the rear Bluetooth® antenna to the mobile phone, which forwards the signals to the mobile telephone network.

Function sequence for comfort telephony (with CODE 856 (Business telephony in rear)) 

The COMAND controller unit sends the switch-on signal (wake-up signal) to the mobile phone as follows:

Rear Seat Entertainment system controller unit→

Rear mobile phone contact plate→

Rear mobile phone cradle

In contrast to basic telephony, the cellular telephone system signals are received in comfort telephony over the following path (and sent the opposite way):

Multifunction antenna →

Mobile phone and stationary heater radio remote control antenna splitter (with code B24 (Remote control for stationary heater)), up to 31.05.2016 →

Rear cellular telephone system antenna amplifier/compensator (as of 31.05.2016 with code 374 (Additional telephone module with Bluetooth® (SAP profile))) →

Rear mobile phone contact plate →

Rear mobile phone cradle (accessories) →

Mobile phone

If the mobile phone is connected with the Rear Seat Entertainment system controller unit, the rear Bluetooth® antenna receives the incoming signals over Bluetooth® from the mobile phone, and forwards them to the Rear Seat Entertainment system controller unit.

If the mobile phone is connected to the COMAND controller unit, the Bluetooth® antenna receives the incoming signals over Bluetooth® from the mobile phone, and forwards them to the COMAND controller unit.

The outgoing signals are sent the opposite way to the mobile phone.

Model 222 up to model year 2018 with code 374 (Additional telephone module with Bluetooth® SAP) with code 856 (Business telephony in rear passenger compartment)

Model 222 up to model year 2018 with code 379 (Telephone module with Bluetooth® (SAP profile)) with code 856 (Business telephony in rear passenger compartment) Instead of the rear mobile phone cradle (accessories) with the mobile phone, a telephone module with Bluetooth® (SAP) can also be plugged into the rear mobile phone contact plate. With the front mobile phone system, the telephone module with Bluetooth® (SAP profile) can both be plugged onto the mobile phone contact plate (X237/1) and onto the rear mobile phone contact plate. If the telephone module with Bluetooth® (SAP profile) is plugged onto the rear mobile phone contact plate, it can be connected to the Rear Seat Entertainment system controller unit or the COMAND controller unit. 

The Rear Seat Entertainment system controller unit charges the mobile phone over the following path:

• Rear mobile phone contact plate
• Rear mobile phone cradle

Function sequence for connection assumed from front mobile phone system 

If a telephone call is accepted or connected by the front mobile phone system, and then transferred to the rear mobile phone system, the Rear Seat Entertainment system controller unit receives the incoming telephone or Internet signals over MOST from the COMAND controller unit. Incoming signals are output in the rear and outgoing signals are read-in in the rear. The Rear Seat Entertainment system controller unit sends the outgoing telephone or Internet signals over MOST to the COMAND controller unit.

Function sequence for connection transferred to front mobile phone system 

If a telephone call is accepted or connected by the rear mobile phone system, and then transferred to the front mobile phone system, the Rear Seat Entertainment system controller unit sends the incoming telephone or Internet signals over MOST to the COMAND controller unit. The Rear Seat Entertainment system controller unit receives the outgoing telephone or Internet signals over MOST from the COMAND controller unit and sends them accordingly to the mobile telephone network.

Function sequence for making calls in "Handset mode" 

The Bluetooth® interface in the rear handset receives the incoming telephone signals over the rear Bluetooth® antenna from the Rear Seat Entertainment system controller unit. The rear handset sends the outgoing telephone signals over the rear Bluetooth® antenna to the Rear Seat Entertainment system controller unit.

The incoming signals are not output over the speakers in the rear and the outgoing signals are not read in over the left rear hands-free system microphone and the right rear hands-free system microphone.

The rear handset can also be used to call up stored SMS messages and emails in a connected mobile phone as well as to write and send new SMS messages and emails.

Displays of information on left rear display or on right rear display 

The following information can be shown on the activated left rear display or right rear display:

• Incoming calls
• Address book
• SMS

"Seamless switch" 

"Seamless Switch" provides the following functionality:

• An existing telephone conversation can be continued in hands-free mode (e.g. when getting into the vehicle) if the Rear Seat Entertainment system controller unit is switched on and "Private Mode" is not activated on the mobile phone.
• An existing telephone call can be continued on the mobile phone when leaving the vehicle.
• A switch can be made between hands-free, the "Handset mode" and the "Private mode" on the connected mobile phone.

SMS 

The SMS application allows the user to receive, transmit and manage his/her SMS messages (e.g. to read or delete them). For this, the received SMS messages already stored on the mobile phone as well as all new incoming SMS messages are forwarded to the Rear Seat Entertainment system controller unit.

The following SMS functions are possible:

• Send SMS.
• Receive SMS message.
• Read SMS on display of handset in rear and on activated left rear or right rear display.
• Delete SMS message.
• Inbox list, sorted according to date

The SMS function requires the mobile phone to support the Message Access Profile (MAP). Only newly written or incoming SMS messages can be read on the left rear or right rear display.

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.

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 on the rear handset. The user can manage the entries through a menu. Pressing and holding the number on the keypad of the rear handset (approx. 2 s) dials up the telephone number stored and establishes a connection.

Telephone conference and toggling 

If the connected mobile phone supports the functions, additional calls can be set up or accepted when an existing call is active. In the telephone conference, all the calls are active at the same time, i.e. all the phone callers can speak to each other simultaneously. When toggling only one call is active, and the other calls are put on hold (the connection is maintained, but it is muted). When toggling the user can only speak to the caller with the active call, a switch can however be made between the active call and the one on hold, thereby enabling conversation with various users.

Telephone conference and toggling are only possible when the connection was not assumed by the mobile phone system.

Address book 

The address book contains the address entries stored in the Rear Seat Entertainment system controller unit. The user can manage all the contact data in the address book (view, edit, add, delete and create). Address-relevant mobile phone system applications in the rear can be directly started and supplied with the stored data through address book entries. Address entries can only be removed by deleting individual entries or by deleting the entire address book. Address data from external devices (e.g. PDA, notebook) can be copied into the address book through the rear Bluetooth® antenna or the rear USB 1 electrical connector or rear USB 2 electrical connector of the rear USB electrical connector. The address data are then permanently available as an address entry. Read access to the phone book of the mobile phone is provided if the mobile phone supports the Bluetooth Phonebook Access Profile (PBAP).

Address entries can contain the following:

• Last name, first name and company
• Postal addresses (private or business)
• Telephone numbers (several telephone numbers can be saved under one address entry with different symbols)

	Electrical function schematic for rear mobile phone system		PE82.70-P-2080-97SEA
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