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Distance warning system, function - GF54.70-P-2000LEB

MODEL 221 with ENGINE 156, 272, 273, 275, 629, 642 with CODE (239) Autonomous intelligent cruise control Plus Light as of Model Year 2010 /CY 09 model refinement package 

View of instrument cluster (A1) distance warning, active 

Fig 1: View Of Instrument Cluster (Distance Warning Active)
G07593996Courtesy of MERCEDES-BENZ USA

Function requirements for proximity warning system (AWS), general 

Proximity warning system, general 

The proximity warning system is an additional function in Plus Light adaptive cruise control, which is controlled by the radar sensors control unit (SGR) (N62/1). It warns the driver in the speed range of 30 to 250 km/h of moving or stationary obstacles in his lane

Proximity warning system, function sequence 

Irrespective of the Plus Light adaptive cruise control, the driver can activate or deactivate the distance warning separately using the left and right multifunction steering wheel button group (S110, S111) in the "Assistant" menu in the instrument cluster (A1). Thus the distance warning system is dependent here on the function (function requirements) of the radar system.

When distance warning is activated, the distance warning readiness indicator is illuminated at the bottom left next to the electronic speedometer (A1p8).

The instrument cluster's multifunction display (A1p13) shows the host vehicle, the set target distance and the vehicle in front with its current proximity.

The distance warning is triggered when a critical traffic situation is detected. This could be, e.g. when the vehicle is being driven at a high speed and the potential party involved in an accident would be impacted in <2.5 s.

A distance warning can be issued for mobile and stationary obstacles. Distance warning is indicated by the DTR warning lamp lighting up and an intermittent tone.

IMPORTANT

The distance warning system does not perform any control functions by itself, such as braking the vehicle.

With the DTR distance potentiometer (N72r1), the specified distance from the vehicle in front can be set in six steps between about 1.0 and 2.0 s, depending on vehicle speed. In the third stage, at a speed of 100 km/h, this is equivalent to a specified distance of approx. 42 m. The specified distance is converted from seconds to meters to match the host vehicle's speed and then shown in the form of a white line in the instrument cluster's multifunction display.

The target distance in the distance indicator matches the current vehicle speed without the driver having to adjust the DTR distance potentiometer.

As an additional function, the driver is alerted if he/she remains within a distance <0.9s from the preceding vehicle for longer than 3s. Here the DTR warning lamp is illuminated until the correct distance is obtained again

This gives the driver the opportunity of avoiding a fine (for leaving insufficient distance to the vehicle in front).

  Instrument cluster, component description A1
Model 221.0/1 except 221.095/195
GF54.30-P-6000LE
  Component description for radar sensors control unit N62/1 GF30.30-P-3301LEC