audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

ABOUT US
General notes on information exchange > < Technical data

A4 Mk3

Components used
Components used
As the individual vehicle systems are networked, the ACC uses a large number of different control units.
These control units communicate with each other across different types of bus. The data bus diagnostic interface -J533-, which is connected to all the different bus versions, prepares and transmits the data to the corresponding control unit.
The control units shown in the illustration are required for the ACC functionality. The control units shown with a black dot are responsible for the core functionality. The other control units handle the visual and acoustic output of information and error messages and deactivate the ACC immediately in the event of an unresolvable error.
   
 - Adaptive cruise control unit -J428-
 - Engine control unit -J623-
 - Automatic gearbox control unit -J217- (only fitted optionally in vehicle)
 - Airbag control unit -J234-
 - Data bus diagnostic interface -J533-
 - Display unit for front information display and operating unit control unit -J685-
 - Control unit for front display and information control panel -J523-
 - Multimedia system operating unit -E380-
 - Trailer detector control unit -J345- (only fitted optionally in vehicle)
 - Convenience system central control unit -J393-
 - Onboard supply control unit -J519-
 - Steering column electronics control unit -J527-/steering angle sender -G85-
 - Cruise control system switch -E45-
 - Control unit in dash panel insert -J285-
 - Steering angle sender -G85-
 - Control unit for electromechanical parking brake -J540-
 - Active steering control unit -J792- (only fitted optionally in vehicle)
 - ABS control unit -J104-

  Note
Some of the control units are only fitted optionally in the vehicle and are therefore only required for the ACC functionality if they are fitted.
Bus networks (the colour pattern shows which bus connects which components)
   
Pink -CAN running gear
Orange -CAN drive train
Grey -CAN extended
Green - MOST bus
Yellow -CAN convenience
Black -CAN diagnosis

Information from senders to individual control units
The ACC also draws on these communication paths to access the information transmitted by various senders to the control units specified above.
   
ComponentDesignation
-G17-Ambient temperature sensor
-G44-Rear right speed sensor (on four-wheel drive vehicles only)
-G45-Front right speed sensor
-G46-Rear left speed sensor (on four-wheel drive vehicles only)
-G47-Front left speed sensor
-G85-Steering angle sender
-G202-Yaw rate sender
-G259-Right adaptive cruise control sender

   

General notes on information exchange > < Technical data