Blind Spot Monitoring Radar Sensor Controller Unit, Basic Function - GF54.71-S-9891A

Model All (Light transporter) 

With Code JA7 (Blind Spot Monitoring) 

Example illustration of blind spot monitoring radar sensor controller unit 

Courtesy of MERCEDES-BENZ USA

Overview 

This document contains information on:

• General 
• Function 

General 

The outer rear radar sensors are located on the left and right behind the rear bumper.

Blind spot monitoring sensor positions and detection ranges 

Courtesy of MERCEDES-BENZ USA

Function 

The sensors of the Blind Spot Assist system are integrated into the side of the rear bumper. The signaling to the driver takes place visually via illuminated symbols in the outside mirrors and acoustically via a warning tone.

The radar sensor transmits bundled electromagnetic waves as so-called primary signals. Objects in the detection range of the radar sensor reflect these electromagnetic waves. The radar sensor receives the reflected electromagnetic waves (secondary signals) and evaluates them according to various criteria. From this, various information is obtained about the objects.

• Angle or direction to the object
• Distance to the object
• Speed differential

The outer rear radar sensors are connected to the network architecture of the vehicle.

The outer rear radar sensors operate according to the master/slave principle. The master or slave function can be determined via the connector coding. The master function is defined for the right rear radar sensor. In other words, the left rear radar sensor sends its information to the right rear radar sensor. The right rear radar sensor evaluates the information from both rear radar sensors and sends corresponding requests and data.