Deactivation of Adaptive Headlights Function In Response To System Faults

Until 09/2007, a system fault will be indicated by the indicator lamp on the light switch flashing.

From 09/2007 system fault will be indicated by a Check-Control message in the instrument cluster.

Dazzling of oncoming traffic must be prevented in the event of a system fault.

For this reason, the adaptive headlights function is deactivated as follows:

• If the stepper motors are still functional, the headlights are returned to the straight-ahead position. The headlights are no longer moved towards bends in the road.
• If it is no longer possible for a headlight to be moved back to the straight-ahead position, the headlight is tilted downwards (by the stepped motors for automatic headlight-range adjustment). This prevents dazzling of oncoming traffic.
• Vehicles up to 09/2007 

  If the headlight cannot be tilted downwards, the bi-xenon bulb in this headlight is disabled as follows:

  When the vehicle is parked up, the control unit registers sleep mode for the adaptive headlights, as follows: Vehicle standstill and terminal R OFF for several minutes.

  The next time the vehicle is restarted, the bi-xenon light of the defective headlight is not switched on.

  The front foglights are switched on in order to ensure a minimum level of illumination.

  The dipped beam headlights are not  switched off while the vehicle is in motion.