FUNCTIONS IN THE AUDIO MODULE (AUD) Volvo XC90 I рестайлинг

FUNCTIONS IN THE AUDIO MODULE (AUD)

The audio module (AUD) can run a number of different functions, but these functions can also be activated by other nodes. An example of these functions is lowering and increasing the volume. The signal comes from the infotainment control module (ICM), but it is the audio module (AUD) that actually changes the volume. The functions are described below.

Functions in the audio module (AUD)

1. Adjustable volume , raises and lowers the volume
2. Adjustable bass , raises and lowers the bass level
3. Adjustable treble , raises and lowers the treble level
4. System generated sound signals , assists other nodes in the system with single sound signals generated in the control module, for example alarm signals for the reverse (reverse) warning function
5. Limiter , the limiter function in the control module does not permit an increase in the power output level if this leads to a fall in sound quality
6. Mixing , mixing allows numerous different sound types to be mixed. In this case, the different sound types are foreground noise, background noise and system generated sound signals. An example of this is where a CD is playing (background noise) and the carphone rings (foreground noise). The ringing signal will be heard through the loudspeakers while the volume of the music drops at the same time
7. Digital bass speaker output , the control module transmits sound signals to the bass speakers via the MOST network. The signal is processed in the audio module (AUD) before it is transmitted on the MOST network to the subwoofer module (SUB)
8. Bass compensation , the bass from the control module is compensated or modified depending on the volume level and the speed of the car. If the vehicle speed and volume level changes, the bass compensation is also changed
9. Treble compensation , the treble in the control module is compensated or modified depending on how the volume is changed. If the volume changes, the treble compensation also changes
10. Equalizer setting, sound compensation , there are different settings for the sound from the audio module (AUD). This compensates for factors such as the location of the loudspeakers and the layout of the car interior
11. Dolby ProLogic II , a surround decoder for sound reproduction.

There are two types of sound, foreground sound and background sound. The sounds which are foreground and background are listed below.

Foreground sound

1. telephone calls
2. carphone settings (setting the ring signal)
3. navigation
4. system generated sound from the audio module (AUD) (different types of alarm sound)
5. traffic messages.

Background sound

1. analogue radio, AM/FM
2. digital radio, DAB
3. CD player
4. MD player.

The functions in the different versions of the audio module (AUD) are

Performance

1. adjustable volume
2. adjustable bass level
3. adjustable treble level
4. system generated sound signals
5. limiter.

High Performance

1. adjustable volume
2. adjustable bass level
3. adjustable treble level
4. system generated sound signals
5. limiter
6. mixing
7. digital bass speaker output
8. bass compensation
9. treble compensation
10. equalizer.

Premium Sound

1. adjustable volume
2. adjustable bass level
3. adjustable treble level
4. system generated sound signals
5. limiter
6. mixing
7. digital bass speaker output
8. bass compensation
9. treble compensation
10. equalizer
11. DPL2 - Dolby ProLogic II.

Scheme 117

Two pairs of loudspeakers and one center loudspeaker can be installed in the car.

The two pairs of loudspeakers are

1. front loudspeakers in the front doors
2. rear loudspeakers in the rear doors.

The center loudspeaker is positioned in the middle of the dashboard.

In some versions of the audio module (AUD), a treble speaker can be connected to the front and rear speakers. The treble speakers for the front loudspeakers are positioned in the front door at the same height as the door mirrors. For the rear loudspeakers, the treble speakers are positioned in the D-post.

The three audio module (AUD) versions have different loudspeaker arrangements

Performance

1. one pair of front bass speakers
2. one pair of rear loudspeakers.

Each loudspeaker consists of a transducer for the entire frequency range. There are no treble speakers connected to this version.

High Performance

1. a pair of front bass / mid-range loudspeakers with treble speakers
2. a rear pair of loudspeakers (coaxial*) with treble speakers.

The front treble speakers are electrically connected to the same signal cable as the front loudspeakers. The rear treble speakers are electrically connected to the rear loudspeakers.

Premium Sound

1. a front pair of 3-way loudspeakers (consisting of a pair of 2-way loudspeakers with treble speakers)
2. a rear pair of loudspeakers (coaxial*) with treble speakers.
3. a centrally-mounted loudspeaker in the dashboard.

The front treble speakers are electrically connected to the same signal cable as the front loudspeakers. The rear treble speakers are electrically connected to the rear loudspeakers.

*Consists of one bass and one treble transducer integrated in the same unit.

TABLE OF LOUDSPEAKER ARRANGEMENTS

Scheme 118

Depending on the version of the audio module (AUD), two headset panels can be installed. The panels have two headset sockets each giving a total of four headset sockets.

Each headset socket has a SEL. button which is used to select the sound source, such as CD player, MD player and radio.

Each headset output also has buttons to select the previous and next track or one of the pre-programmed radio channels. The buttons are internally connected to a resistor stage. When the buttons are pressed, different voltages levels are produced. These voltages are interpreted by the control module as three different selections. When any of the buttons are pressed, this data is transmitted to the audio module (AUD). The module then transmits the data via MOST network to the infotainment module (ICM). The infotainment control module (ICM) then changes the track or sound source.

Each headset socket has a volume control which can be used to change the sound level in the headset. The headset panels are in the left and right-hand C-posts.

If a sound source, which has already been selected via the infotainment control module (ICM), is selected the track or radio channel for this sound source cannot be changed via the headset output. There is no difference in priority between the headset outputs. This means that the radio channel or track can be changed via the headset output for a sound source which is being used by another headset output. All headset outputs with the same sound source then change radio channel or track.

The signals to the headset sockets and the buttons on the headset panel are directly connected to the audio module (AUD).

Scheme 119

All versions of the audio module (AUD) have a microphone which is directly connected to the control module. The microphone is installed in the rear view mirror.

The microphone is used for functions such as handsfree in the phone module (PHM).

This function can be used to read parameters, status identifiers and counters stored at the same time as a diagnostic trouble code (DTC). These are called frozen values.

For further information, see DESCRIPTION OF VEHICLE COMMUNICATION INFORMATION .

New software can be downloaded into the audio module (AUD). When ordering software, the hardware and the software in the car is compared to the information in the Volvo central database. If the comparison is OK the software is downloaded to the control module.

If the comparison between the car and Volvo central database is not OK, the database is updated with the car configuration. When this is complete the software is downloaded.

The control module is under the right-hand front seat. The seat must be removed to replace the control module

After replacing the control module, the unique serial numbers of the control module are checked by the infotainment control module (ICM). The installed control module will not work if the serial number is incorrect.

Try turning the ignition off and on if there are problems after the software is downloaded and the control module is not working.

The MOST network is used for a total software reload.

Scheme 120

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

To play back sound, a control module transmits a request to the infotainment module (ICM) (16/1). The infotainment control module (ICM) distributes the request to the audio module (AUD). The control module is then able to transmit signals via the MOST network to the audio module (AUD).

The infotainment control module (ICM) (16/1) processes changes to the sound, balance, bass, treble and equalizer settings. It transmits the changes via the MOST network to the audio module (AUD) (16/105) which then carries out the changes.

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

1. the antenna module (ATM) (16/110) for AM/FM radio
2. the antenna module (ATM) (16/110) for digital radio, DAB
3. the phone module (PHM) (16/60) for handsfree calls
4. multimedia module (MMM) (16/108) for voice guiding (navigation)
5. the MD module (MP1) (16/107) for minidiscs
6. the CD module (MP2) (16/106) for compact discs.

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) to the audio module (AUD).

When the audio module (AUD) has received optical signals on the MOST network, these signals are sent onwards as analog signals to the directly connected front (16/4, 16/3) and rear (16/6, 16/5) loudspeakers. Certain versions of the control module have several directly connected components such as front treble speakers (16/55, 16/56), D-post loudspeakers (16/58, 16/57), center loudspeaker (16/26) and headset sockets (16/111, 16/112). The control module transmits analog signals to these components.

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).

Certain versions of the audio module (AUD) can also generate a digital subwoofer signal from the signal transmitted to the audio module (AUD). This signal is then transmitted via the MOST network to the subwoofer module (SUB) (16/79). The signal which is transmitted from the audio module (AUD) to the subwoofer module (SUB) is a summated and filtered loudspeaker signal.

The bass speaker signals are transmitted from the audio module (AUD) on a dedicated channel on the MOST network.

When the MOST network starts after the ignition is switched on, the infotainment control module (ICM) transmits data to the audio module (AUD) indicating whether or not there is a subwoofer module (SUB) available on the MOST network.

Scheme 121

There are two identical button arrangements (16/111, 16/112) on the headset panel, one for each socket. These buttons are used to change the sound source and track.

When a button is pressed on the headset panel, the audio module (AUD) identifies which button it was. This signal is transmitted between the headset panel and the audio module (AUD) on a directly connected cable. The audio module (AUD) (16/105) then sends the data onwards via the MOST network to the infotainment control module (ICM) (16/1) which in turn transmits the data onwards to the selected sound source.

The sound sources which can be selected are

1. radio (ATM) (16/110)
2. CD player (MP2) (16/106)
3. MD player (MP1) (16/107).