Telephone Mode, Function

Block diagram COMAND telephone system, illustrated with the following equipment:
- Sound system (code 810)
- Voice control system (VCS) (code 813b)

Abbreviations:
CAN = Controller area network
D2B = Digital data bus
X11/4 = Data link connector

NOTE: The marked components are the primary components for telephone operation.

The telephone system can be controlled directly on the COMAND operating, display and control module (A40/3n1) via the multi-function steering wheel in combination with the multi-function display in the instrument cluster (A1) or via voice control (optional).

Telephone operation
The data telegrams (e.g. dialing telephone number) for control of the telephone system are transferred to the COMAND operating, display and control module (A40/3n1) via the digital data bus (D2B) and D2B cellular telephone interface (A59/1). The A59/1 interface transfers the data telegrams to the cellular telephone via a separate interface.

The actual telephone connection is completed via the cellular telephone and rear bumper antenna (A2/31). This antenna is simultaneously the substitute antenna for the emergency call system. For this reason the A2/31 antenna is connected directly to the emergency call control module (A35/8). An RF relay integrated into the A35/8 module completes the connection to the A2/31 antenna and cellular telephone as required.

NOTE: When the telephone is in use the current audio source is automatically muted.

Hands-free feature
The voice signal from the driver is converted into an electrical signal by the hands-free microphone (B25) and transferred to the cellular telephone (A34/6) vis the D2B cellular telephone interface (A59/1). The voice signals from the party at the other end of the line are transferred to the D2B bus from the A59/1 antenna and received by the audio components of the COMAND operating, display and control module (A40/3n1). Here the signals are amplified and output on the vehicle loudspeakers.

NOTE: If the vehicle is equipped with sound system (code 810) the voice signals are received by the sound amplifier (A2/13), amplified and then output on the vehicle loudspeakers.

The COMAND operating display and control module (A40/3n1) has the following telephone functions;

- Direct entry of telephone number with dial or number keys, display of name of party called (if number entered is stored).
- Quick dial: Selection of the first 10 memory locations is possible with one key only, selection of all other memory locations possible by entering the three-digit memory location number.
- Disabling of telephone system (lock/unlock)
- Sorting possibility for memory locations according to;
- Memory location number or
- name (alphanumerical) or
- last 10 numbers called.