Component Description For Intelligent Radar Sensor Control Unit - GF30.30-P-3305FQ

MODEL 218

with CODE 234 (Blind Spot Monitoring)

Rear bumper, MODEL 218.3

Fig 1: Intelligent Radar Sensor Control Unit Components Location - Model 218 Code 234

Courtesy of MERCEDES-BENZ USA

Location

The rear bumper radar sensors are mounted on the left and right on the inner side of the rear bumper

Tasks

The rear bumper radar sensors recognize vehicles in the blind spot. The rear bumper radar sensors are ultra wideband radar sensor with the following properties:

Detection range: s = 0.18 to 30 m, for a resolution of s = 0.04 m
Detection angle of ∠ = 60° with angle measurement and ∠ = 130° with detection only
Carrier frequency: f = 24.125 GHz (up to 28.02.2013) or f = 25 GHz (from 01.03.2013)
Method of operation: short pulse process with a f = 5 GHz bandwidth (up to 28.02.2013) or f = 1.4 GHz bandwidth (from 01.03.2013)

The rear bumper 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 bumper radar sensor. That means that the rear left bumper radar sensor transmits its information via the front end CAN (CAN G) (up to 28.02.2013) or chassis CAN 1 (CAN E1) (from 01.03.2013) to the rear right bumper radar sensor. The rear right bumper radar sensor evaluates the information from both rear bumper radar sensors and transmits the appropriate requests or data via the front end CAN (up to 28.02.2013) or chassis CAN 1 (from 01.03.2013) to the affected control units.

To achieve this the rear bumper radar sensors fulfill the following tasks:

Reading in sensors and signals
Evaluation of input factors
Output of signals

Reading in sensors and signals

The rear bumper radar sensors receive the following information via the front end CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013):

Terminal status of terminal 15
Status of engine timing
Status of function "Blind Spot Assist"
Wheel speeds and wheel rotation direction
Global Positioning System (GPS) signals
Turn signal lights status

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Evaluation of input factors

The input factors are evaluated by the integrated microprocessors and the relevant assembly parts are then actuated.

Output of signals

The rear left bumper radar sensor transmits the following signals via the front end CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013):

Blind Spot Assist warning output, request
Operating condition, status

The rear right bumper radar sensor transmits the following signals via the front end CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013):

Issue acoustic warning request
Display request message
Request for the left Blind Spot Assist warning lamp (M21/1e2) and the right Blind Spot Assist warning lamp (M21/2e2)

The left rear bumper radar sensor transmits recorded data or status information via the front end CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013) to the right rear bumper radar sensor which uses this to generate the requests for emitting a warning.

Blind Spot Assist wiring diagram

PE54.71-P-2100-97XAA