Brief component description: Headunit

WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

In principle, the structure of the headunit corresponds to that of a personal computer. Like a personal computer, the headunit contains the following components:

Processor
Working memory
Hard disk
Fan

The hard disk in the headunit is used to store the application software and other data.

The following applications are installed on the hard disk:

Music library
The music collection is based on the audio data stored on the integrated hard disk.
Music track database
Software for track identification using a music track database (Gracenote®).
Navigation system (map data) and software (application software)
Full screen display possible: Zoomable assistance window with map view, journey planner, map data storage on the hard disk.
Voice processing system
Office (database with addresses)
The data is used for telephone and navigation, for example.

The headunit is the central control unit for the listed applications. For the purposes of picture signal transmission, the headunit is linked to the Central Information Display (CID). The headunit is also connected to the controller (CON). The controller (CON) is the control panel for the Central Information Display (CID).

Fig 1: Display - Central Information Screen (CID)

Courtesy of BMW OF NORTH AMERICA, INC.

Item	Explanation
1	Central information display (CID)
2	Rotary push-button
3	Headunit drive
4	Eject button for DVD and CD
5	Search button, backwards and forwards
6	Freely programmable favorite button
7	Control panel for integrated automatic heating and air-conditioning system (IHKA)
8	Button for traffic reports (TP = Traffic Program, depending on the country)
9	Modus button (changeover of audio source)