Function Description

Function Description

Activating

To activate the high beam assistant, set the headlamp switch (E1) to AUTO and then push the turn signal switch (E2) one time to the front. The steering column electronic systems control module (J527) recognizes the position of the turn signal switch and sends the message to the vehicle electrical system control module (J519) via the CAN Bus Comfort.

The headlamp symbol in the instrument cluster will illuminate with an "A" to let the driver know the high beam assistant is on. When the high beams are on, the blue high beam symbol also comes on.



Functionality

The base of the interior rearview mirror has a camera with CMOS images sensors, which also switch on and off the low beam (see chapter 2) and the high beam. The electronics, automatic high beam control module, are integrated in the automatic dimming interior rearview mirror.

The CMOS camera takes a white and red picture of the actual traffic and ambient conditions. The automatic high beam control module evaluates the information and switches the high beams on or off.

If passing or approaching vehicles are recognized, the CAN Bus sends the request to the vehicle electrical system control module to switch off the high beam. A request to switch off will also be sent if a specific minimum vehicle speed is not reach or if the ambient brightness exceeds a set limit because of the daylight or bright street illumination. If there are no switch off conditions present, then a switch off request will be sent.

The vehicle electrical system control module controls the bulbs for the left and right high beam headlamps as well as the left and right low beam reflector motors based on the high beam recommendation sent from the automatic high beam control module when the automatic high beam switch-on is activated and the vehicle road speed exceeds a defined value and the vehicle electrical system control module simultaneously gives the command to the rain/light recognition sensor to switch on.

If the rain/light recognition sensor does not send the switch-off command, then the high beams are not controlled. If the high beams were switched off by the high beam assistant, and if the rain/light recognition sensor sends the command to switch off the low beams then the high beam is no longer controlled.

The driver can then manually switch the high beams on or off.

If the automatic high beam control module sends a switch-off command, the driver can switch the high beams back on by pushing the turn signal switch forward one time. The high beam assistant is now temporarily deactivated. Pushing the turn signal switch forward one more time will activate the high beam assistant again. If the driver pulls the turn signal switch after the temporary deactivation, the high beams will be switched off and the high beam assistant remains deactivated.

If the high beam assistant switches on the high beams, the driver can switch them off by pulling the turn signal switch one time. The high beam assistant will remain deactivated. If the driver pushes the turn signal switch forward one time when the high beams are on, then the high beam assistant will be deactivated temporarily and the high beams remain on. When the turn signal switch is pushed again, the automatic high beam is activated. If the turn signal switch is pulled once again after it was temporarily deactivated, then the high beam assistant is deactivated permanently.






E1 - Headlamp Switch

E2 - Turn Signal Switch

J285 - Instrument Cluster Control Module

J519 - Vehicle Electrical System Control Module

J527 - Steering Column Electronic Systems Control Module

J533 - Data Bus On Board Diagnostic Interface

J844 - Automatic High Beam Control Module

A - CAN Bus Comfort

B - Wire Connection

C - LIN-Bus

D - CAN Bus Extended

E - Instrument Cluster CAN Bus/Chassis