Safety Warning
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Long-Range Radar Sensor, Component Description - GF30.30-P-3125LF
Model 217, 222
up to model year 2018
with code P20 (Driving Assistance package Plus)
Shown on model 222
Location
The front long-range radar sensor is located in the center, in front of the radiator.
Tasks
The long-range radar sensor has the following tasks:
- Actuation, power supply and evaluation of target data from the integral long range radar
- Transmission of data for longitudinal directional vehicle control to the radar sensors control unit (N62/1)
- Transmission of data for longitudinal directional vehicle control to the radar sensors control unit
- Transmission of object data to the radar sensors control unit for plausibility checking of the object data from the stereo MFK (A40/13)
- Transmission of object data for collision-avoiding intervention by the brake system to the radar sensors control unit
The control electronics integrated in the long-range radar sensor actuate the long range radar and evaluate the target data. The object data from the long range radar are transferred from the front long-range radar sensor via the chassis FlexRay (Flex E) to the radar sensors control unit.
Input and output signals
The long-range radar sensor transmits and receives the following signals via the chassis FlexRay:
- Input signals
- Output signals
Input signals
- Radar request
- Diagnosis request
Received signals are evaluated by the integrated control electronics.
Output signals
- Target data from the radar
- Diagnostic data
Structure
The front long-range radar sensor contains control electronics for actuating and evaluating the long range radar.
Properties of the long range radar:
- Detection range of the long range radar sensor:
- s < 30 m with a detection angle of ∠ = 30°
- s = 30 to 100 m with a detection angle of ∠ = 16°
- s = 100 to 200 m with a detection angle of ∠ = 12°
- Carrier frequency: 77 GHz (in accordance with the "Pulse Doppler Principle" for independent measurement of distance and speed)
The front wide range radar sensor must be readjusted using the integrated "Service Adjustment Mode" after replacement (e.g. after an accident repair).
| Wiring diagram for Distronic (DTR) control unit | Engine 157, 276, 277, 278, 279, 642.8, 651 in model 222 up to model year 2018 with code P20 (Driving Assistance package Plus) Control unit B29 Engine 157, 278, 279 in model 217 up to model year 2018 with code P20 (Driving Assistance package Plus) Control unit B29 |
PE30.30-P-2101-97SEA |
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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