Headunit Basic Version (HU-B)
HU-B
Headunit basic version (HU-B)
As headunits, control units from different system suppliers can be used. In recent years the entire series included the following:
Headunit High (Navigation Professional):
- High-Variant Car Information Computer (CIC)
- Car Communication Computer (CCC)
Headunit Basic Version (Navigation Business)
- Basic Variant Car Information Computer (CIC)
- 2nd generation Central Headunit and Multimedia Platform (CHAMP)
- Multi-audio system controller (MASK)
Radio (no navigation)
- Headunit basic version (HU-B)
- Radio Professional (RAD2)
- Radio Business (RAD)
The headunit basic version (HU-B) is described below.
The HU-B control unit is used as a headunit. The headunit basic version is the headunit in the MOST network.
The noticeable changes for the headunit basic version are:
- Central Information Display connected via APIX data line (previously LVDS data line)
- Diversity (aerial amplifier without aerial diversity; aerial diversity integrated in the headunit)
- New controller with only 5 selector keys and one tilt direction
- Integrate of the following former control units as functions in the head unit:
- Digital tuner (DAB)
- Digital tuner US (IBOC)
- Satellite car radio (SDARS)
- Integrated telephone function (depending on optional equipment)
Brief component description
The following components are described:
- HU-B
- Central Information Display with APIX interface
- Controller
- USB connection
HU-B: HU-B
The headunit basic version (HU-B) has 8 freely programmable favorite buttons.
The audio operating facility and climate operating facility are connected electrically to the integral automatic climate control (IHKA). A local interconnect network bus is used here. The operating facilities take their power supply and ground connection from the IHKA with terminal 30F.
In principle, the structure of the HU-B corresponds to that of a PC (personal computer). Similar to a PC the headunit basic version includes:
- Processor
- Working memory
- Other periphery such as a DVD drive
The headunit basic version (HU-B) is connected to the diagnosis socket via Ethernet. The software can thus be reprogrammed during service operation.
Because of the extended functionality, the connections on the rear of the headunit basic version have changed.
The headunit basic is available in different versions (depending on vehicle equipment, national-market version, for example).
The following graphic shows for example possible connections on the rear side of the headunit basic.
Central Information Display with APIX data line
The central information display (CID) is a graphic display unit.
The Central Information Display is a display with combined technology from the LCD and TFT (LCD = liquid crystal display, TFT = thin-film transistor). The central information display has backlighting by means of LEDs.
The central information display is connected directly to the headunit via an APIX data line. The central information display represents image data supplied by the headunit. With this technology the central information display no longer has a CAN connection. Thus the central information display is no longer a control unit in the diagnostic range.
The Central Information Display is supplied with voltage via the headunit. The positive connection (9.5 volt) is switched via the headunit.
The Central Information Display is connected to the headunit via the APIX data line (automotive pixel link).
CON: Controller
The controller is the central operating element for the vehicle functions that can be selected and configured on the central information display. The control panel and control unit of the controller (CON) have been combined in one single component.
There are 5 fixed selector keys arranged around the controller. These selector keys now enable selection of half of all the submenus.
The controller is connected via the bus system with the headunit.
Signal path: Controller (CON) > K-CAN > Front Electronic Module (FEM) > K-CAN2 > Headunit Basic Version (HU-B)
The signal for the locator lighting (terminal 58g e.g. for the buttons) is transferred on the bus.
USB connection
NOTICE: No import is possible via the USB audio interface.
It is not possible to import data via the USB audio interface on the centre console. This interface is still only intended for playback of external audio sources.
USB sticks with the standard USB 1.1 are supported. However, the standard USB 2.0 (= high speed) is recommended. If the USB stick has been partitioned, the files must be located on the first partition. This is the only way these files are recognised and used. The USB interface supplies the USB stick with a maximum of 500 mA.
USB hard disks, USB hubs and USB memory card readers with a number of bays cannot be read at the USB interface.
AUX-IN connection
The audio socket (AUX-IN connection) is used to connect an external audio source (e.g. MP3 or CD player) via a 3.5 mm jack plug. The unit is operated on the operating elements of the external audio source.
The AUX-IN connection with USB port (SA6FL USB audio interface) is available as optional equipment. External audio sources with a USB port are integrated into the entertainment system of the vehicle via this USB audio interface.
If an external audio source is connected to the AUX-IN connection via the jack plug, the audio data are transferred to the headunit via an audio line. The audio source is selected via iDrive. The music tracks are selected on the external audio source.
System functions
The following system functions are described:
- Functional networking
- Functional enhancements of the HU-B
- Integrated telephone function
- Personalization of settings
Functional networking
A complex system network with distributed functions residing in additional control units is needed to implement the head unit's functionality. The following graphics show the functional networking.
Functional enhancements of the headunit basic version
Combining several devices that were previously external in one housing has resulted in the following benefits:
- Additional functionality
- Software is easy to extend using suitable interfaces
- Fewer plug-in connections, therefore fewer fault sources
- Optimised installation room and lighter weight
The HU-B has a modular structure. The most important systems for communication are integrated in the HU-B as modules. The HU-B combines the following components in a housing:
- Tuner (FM)
- Tuner (AM)
- Diversity aerial
- DAB tuner (L band and band III)
- IBOC decoder (US only)
- SDARS satellite tuner (US only)
- Audio system controller
- MOST-CAN gateway
- Interface to the Central Information Display (APIX)
The CD drive is suitable for playing CDs (digital audio). Both the MP3, WMA and AAC formats (m3a, m3p from iTunes) are supported.
Integrated telephone function
Depending on the configuration of the vehicle, the telephone function is integrated in the head unit. In this case, no separate telephone control unit is installed.
The procedure for Bluetooth pairing of the mobile phone can be found in the owner's handbook.
Pay attention to separate functional description for the\n\n integrated telephone function.
Personalization of settings
For BMW vehicles, the personalization of functions is known as a Personal Profile. Here, individual settings are stored in the vehicle on a key-dependent basis. The settings are called up again on unlocking the vehicle.
The HU-B also supports mobile profile.
With mobile profile the personal profile of the user can be transmitted via the following interfaces:
- External USB memory
- Online via the BMW Portal
Subsequently, the Personal Profile can be imported into another BMW vehicle.
Notes for Service department
Diagnosis instructions
NOTICE: Observe the service function.
A service function in the diagnosis system can be used to reset the settings of the Personal Profile.
Path: Service function > Body > Head unit > Restore delivery status
If "perceived symptoms" is selected, a fault pattern catalogue is available.
Programming information
The following interface is used for programming the headunit basic version (HU-B):
- Ethernet via diagnosis socket
We can assume no liability for printing errors or inaccuracies in this document and reserve the right to introduce technical modifications at any time.