System Overview

System overview

Control module




The accessory USB unit (AUU) is designed to serve as an interface between the vehicle's infotainment system and external USB and iPod devices that support the standard for removable media on USB 2.0.

Examples of USB/iPod devices that support the standard for removable media on USB and 2.0 are:
- Cameras
- MP3 players
- Handheld computers
- Portable USB drives
- iPod G4 from version 3.1.1
- iPod G5 from version 1.2.1
- iPod mini from version 1.4.1
- iPod nano from version 1.1
- iPod Video from version 1.1
The Accessory USB unit (AUU) is located behind the glove compartment down to the left on the cowl panel and the corresponding USB port is located in the centre console.
The accessory USB unit (AUU) has serial optic communication with components on the MOST network. All communication with the accessory USB unit (AUU) is handled via the infotainment control module (ICM).
In order to function in the MOST network, the infotainment control module (ICM) checks that the accessory USB unit (AUU) has a correct serial number. If the number is incorrect, the accessory USB unit (AUU) does not work.
The accessory USB unit (AUU) checks executed activations and input/output signals via its integrated diagnostics. If the control module detects a fault, a diagnostic trouble code is generated. Any diagnostic trouble codes are stored in the control module memory. The information can be read via the data link connector in the vehicle.
For further information, also see Signal specifications.

Signals
The table below summarizes the input signals to and output signals from the accessory USB unit (AUU). The signal types are divided into directly connected signals, serial communication and MOST communication. The illustration below displays the same information with the Volvo component designations.