Playing Back Sound

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2014 Volvo XC90, 2013 Volvo XC90, 2012 Volvo XC90, 2011 Volvo XC90, and 2010 Volvo XC90. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Volvo Component Designations

Courtesy of VOLVO CARS CORPORATION

All functions in the audio module (AUD) (16/105) are controlled by the signals from other nodes in the MOST network.

To initiate audio playback, a control module transmits a request to the infotainment module (ICM) (16/94). The infotainment control module (ICM) allocates the request to the audio module (AUD) then the control module can transmit data via the MOST network to the audio module (AUD).

The infotainment control module (ICM) processes changes to the volume, balance, bass, treble and equalizer settings. The infotainment control module (ICM) transmits the changes via the MOST network to the audio module (AUD) which then carries out the changes.

The control modules on the MOST network which use the audio module (AUD) to play back sound are:

multimedia module (MMM) (16/108) for voice guiding (navigation)
integrated audio module (IAM) (16/1)
Subwoofer module (SUB) (16/79)
phone module (PHM) (16/60), handsfree speaker sound.

The audio module (AUD) can generate simple sound signals which are used for example to warn the driver and passengers if there are problems. These signals are transmitted from the infotainment control module (ICM) via the MOST network to the audio module (AUD).

When the Audio module (AUD) has received optical signals on the MOST network, the signals are transmitted onwards as analog signals to:

loudspeaker left front (16/4, 16/55)
loudspeaker right front (16/3, 16/56)
Loudspeaker left rear (16/6)
Loudspeaker right rear (16/5)
loudspeaker left D-post (16/57)
loudspeaker right D-post (16/58)
Center loudspeaker (16/26) (option).
headset panel, left, rear (16/111)
headset panel, right, rear (16/112).

The microphone (16/77) is directly connected to the audio module (AUD). The microphone transmits analog signals to the control module.

When sound compensation is required, the infotainment control module (ICM) transmits sound compensation signals via the MOST network to the audio module (AUD).