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DISTRONIC Distance-Pilot Controller Unit, Component Description - GF30.30-P-3218FH
Model 238
Up To Model Year 2021
With Code 239 (Adaptive cruise control Pro (DISTRONIC PRO))
Shown on model 238.3
Location
The DISTRONIC Distance-Pilot electric controller unit is located in the middle upstream of the cooler.
Tasks
The DISTRONIC Distance-Pilot electric controller unit assesses the traffic situation ahead of the vehicle through evaluation of the data from the integral long range radar. The detected data serve to implement the following functions:
- CRUISE CONTROL
- Variable speed limiter (except code 494 (USA version))
- Permanent limiter
- Automatic distance control (with code 239 (DISTRONIC Distance-Pilot))
- Change of lane (with code 239 (DISTRONIC Distance-Pilot))
- Speed control (with code 239 (DISTRONIC Distance-Pilot))
- Reeving/control by the person in front (with code 239 (DISTRONIC Distance-Pilot))
- Automated Stop Vehicle (with code 239 (DISTRONIC Distance-Pilot))
The DISTRONIC Distance-Pilot electric controller unit compares the permanent target and actual values with each other and evaluates the respective driver requirements. In order to implement the automatic distance and speed control the DISTRONIC Distance-Pilot electric controller unit sends the respective requests for acceleration, deceleration and switching via the chassis FlexRay (Flex E) after evaluation of all input factors.
This means that the DISTRONIC Distance-Pilot electric controller unit has the following tasks:
- Reading in input factors
- Evaluation of input factors
- Actuation of assembly parts
- Transmission of initial parameters
Reading in input factors
The DISTRONIC Distance-Pilot electric controller unit receives the following input signals via chassis FlexRay, among other things:
- Operating condition for engine/drivetrain
- Gear range engaged
- Parking brake status
- Engine drive torque
- Braking torque
- Acceleration/yaw rate
- Driver request through the cruise control lever (S40/4)
- Driver request to overtake through setting the turn signal
- Vehicle speed/acceleration
- Steering wheel angle
- Brake pedal position
- Accelerator pedal position
Evaluation of input factors
The input factors are evaluated by the microprocessor and the corresponding assembly parts are actuated.
Actuation of assembly parts
The DISTRONIC Distance-Pilot controller unit actuates the radiation dome heater (R61) over a direct line.
Transmission of initial parameters
The DISTRONIC Distance-Pilot electric controller unit sends the following initial parameters via the chassis FlexRay, among other things:
- DISTRONIC Distance-Pilot system status
- Object information
- Request to increase/reduce engine torque
- Request to increase/limit stage
- Request to increase/reduce braking torque
- Request to emit warning tones, system or warning messages
- Requirements for initiating PRE-SAFE® measures
Structure
The DISTRONIC Distance-Pilot electric controller unit contains the following assembly parts:
- Long range radar
- Control unit
Properties of the long range radar:
- Detection range:
- s > 45 m for a detection angle of ∠ = 45°
- s = 45 to 200 m for a detection angle of ∠ = 9°
- Carrier frequency: 77 GHz (in accordance with the "Pulse Doppler Principle" for independent measurement of distance and speed)
The DISTRONIC Distance-Pilot electric controller unit must be newly adjusted after exchange (e. g. after an accident repair) using the integrated "service adjustment mode".
| Wiring diagram for DISTRONIC Distance-Pilot controller unit | PE30.30-P-2107-97DCA |
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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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