Technology & competence

Lane guard system (LGS)

Greater traffic safety thanks to lane monitoring

On long and monotonous routes or during night-time driving, the driver's attention sometimes wanes – or he may even fall asleep for a second. The lane guard system (LGS) monitors whether the vehicle stays in the correct lane, thus ensuring improved safety and driving comfort. If the vehicle leaves its lane without the driver having activated the direction indicators, an acoustic signal sounds to warn the driver.

Function and operation

A video camera behind the windscreen records the lane markings and the vehicle's position in respect of the lane markings. If the vehicle crosses the lane markings without the direction indicators having been activated, the driver is warned by the sound of "rattling nails" from a loudspeaker in the right-hand or left-hand door, depending on which lane marking has been crossed. The system activates itself automatically at speeds over 60 km/h and can be deactivated via a rocker switch. At speeds below 75 km/h, the warning is sounded when the vehicle reaches the inner lane marking and above 75 km/h, it is sounded when it reaches the outer lane marking. If no warnings can be given, e.g. because there are no lane markings, the driver is informed accordingly by means of a check lamp or the Highline display.


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