Two sets of headphones can be connected to separate outputs for sound output at the headphone interface.
The headphone interface (KHI) is a separate control module in the MOST network. The requests for the particular functions can be issued by various control modules.
The headphone interface (KHI) can process two different audio sources with different settings. Audio and control data are supplied via the MOST bus as input signals. The audio signals with the set volumes (voltage value) lie at the two outputs.
Switch blocks are fitted on the left-hand and right-hand sides of the rear center console. The volume at the headphones is set using the volume control button on the switch block. This key corresponds to the right-hand rocker switch (+/-) for volume adjustment on the multifunction steering wheel (MFL).
The K-CAN SYSTEM data bus is the data connection between the instrument cluster and the control modules in the chassis and suspension, drive and body sections. Information is exchanged with data telegrams.
The MOST (Media Oriented Systems Transport) bus links the audio, video and navigation systems. Information relating to function requests is transmitted to the relevant control modules by means of MOST bus messages.
The function of the volume adjustment is the same for both sets of headphones. However, the volume setting is separate for the left-hand and right-hand headphones.
Pressing the 'loud' or 'soft' button on the left-hand switch block changes the volume in the left-hand headphones. Pressing the 'loud' or 'soft' button on the right-hand switch block changes the volume in the right-hand headphones.
Pressing the buttons changes the size of the control signals. A change in the control signals leads to a reduction or enlargement of the audio signals in the headphone interface. Changing the signal size of the audio signals corresponds to a volume change in the headphones.
The headphone interface can be flashed via the diagnosis interface.