Distronic Distance-Pilot, Function - GF30.30-P-3314GWM
Model 463
as of model year 2019
with code EM4 (Driving Assistance package)
Function requirements, general
- No undervoltage or overvoltage
- The Distance Pilot DISTRONIC must be correctly coded.
- Engine running or drive train operational.
- Parking brake not operated
- Gear range "D" engaged (vehicle not in backward movement)
- Vehicle speed v = 0 to 200 km/h and v = 200 to 0 km/h
- Electronic Stability Program (ESP®) not switched to passive mode
- No active ESP® intervention recognized (vehicle not in sliding movement)
- Distance pilot DISTRONIC activated via the variable speed limiter button and distance pilot, the distance pilot switch (luxury variant)/variable speed limiter switch and distance pilot (supersport variant)
- Soiling and function test of DISTRONIC distance pilot control unit successfully completed:
The DISTRONIC Distance-Pilot controller unit performs a soiling and function test to ensure proper operation after each engine start. This assumes an object is in the detection range which can be used as a reference value. If a malfunction is established or there is no object in the detection range of the DISTRONIC Distance-Pilot controller unit, the DISTRONIC Distance-Pilot controller unit cannot be activated.
- Standstill control, enable issued (driver door/driver belt buckle and front passenger door closed)
Distronic Distance-Pilot, function
The DISTRONIC Distronic Distance-Pilot regulates the speed and the distance to the vehicle immediately ahead automatically according to the specification of the driver, in that it brakes when necessary and accelerates again, where possible. Distance and speed control is performed by the DISTRONIC distance pilot control unit. To do so, the DISTRONIC distance pilot control unit actively intervenes in engine management/the brake system. The handling characteristics of the DISTRONIC Distance-Pilot adapt automatically to the selected transmission mode (DYNAMIC SELECT). The chosen transmission mode is sent to the DISTRONIC distance pilot control unit by the DYNAMIC SELECT switch in the lower control panel via LCP LIN, the Audio/COMAND control panel, telematics CAN, head unit, user interface CAN, electronic ignition lock control unit and the suspension FlexRay.
In stop and go traffic the DISTRONIC Distance-Pilot brakes vehicle automatically (if necessary through to a standstill). Once the traffic situation again allows this, the DISTRONIC distance pilot accelerates the vehicle automatically up to the set target speed and therefore frees up the driver from these tiring routine tasks (e.g. frequent starting off and braking in stop-and-go (Stop-and-go pilot).
If the DISTRONIC distance pilot detects that strong braking is necessary (e.g. vehicle cutting in, stationary obstacle), the active brake assist/DISTRONIC distance pilot warning light lights up in the instrument cluster and an intermittent alarm tone sounds. Both require the driver to proceed with increased caution and to possibly also brake himself. If the driver reacts to the acoustic warning and brakes, he will be assisted in this by the Brake Assist. This calculates the required brake force amplification according to the situation. A threatening accident can be prevented under certain circumstances or at least one can mitigate its consequences. If the driver fails to respond to the acoustic warning, the Brake Assist initially initiates (in addition to the warning message and acoustic warning) an automated partial and then maximum full-stop braking.
A reaction to stationary vehicles in the driving lane is possible up to a speed of 60 km/h.
If the DISTRONIC Distance Pilot is switched off, the situation in front of the vehicle will still be monitored and evaluated. In dangerous situations warnings are given, as described above, or there is autonomous braking.
The cruise control subfunction of the DISTRONIC distance pilot is described in separate documents and combines the following areas:
- Automatic speed control
- Variable limiter (except code ZU8 (national version USA))
- Permanent limiter
Representation of the Assist Graphic in the IC (CLASSIC display)
Operation:
The DISTRONIC distance pilot is activated via the variable speed limiter button and distance pilot and the distance pilot switch (sport variane) or via the variable speed limiter button and distance pilot switch (supersport variant) on the steering wheel. The steering wheel electronics reads the control signals directly and sends them to the DISTRONIC distance pilot control unit via the steering wheel CAN, steering column tube module control unit and suspension FlexRay.
Multifunction steering wheel button groups, shown on sport variant, left-hand drive vehicle
Multifunction steering wheel button groups, shown on supersport variant, left-hand drive vehicle
If the LED variable speed limiter lights up, the DISTRONIC Distance-Pilot deactivates and the function of the variable speed limiter is programmed. The steering column tube module control unit directly activates the variable speed limiter light-emitting diode (except code ZU8 (national version: USA)).
Every time the variable speed limiter button and distance pilot, the distance pilot switch (sport variant)/variable speed limiter and distance pilot switch (supersport variant) is activated, the distance to the vehicle in front is displayed in the instrument cluster for t = 5 s.
Through selection of the operating level "DISTRONIC PLUS" in the menu "Assistance" the distance graphic is shown permanently. Display of the distance graphic can be switched on or off independently of the activity of the automatic distance control. The distance to the vehicle driving immediately ahead can be switched on or off via the DISTRONIC control in seven stages between about t = 1.0 and 2.0 s.
Display from the DISTRONIC Distance-Pilot in IC, shown on Tacho display Sport
If a vehicle driving immediately ahead is recognized on the lane or on the fast lane, the segments also light up the segments in the speedometer.
The DISTRONIC distance pilot is shown by way of example in the following processes and properties:
- Activate DISTRONIC Distance-Pilot and drive off automatically
- Automatic distance control
- Speed control
- Going back into a lane/person in the front regulation
- Automated Stop Vehicle
- Limits of the DISTRONIC Distance-Pilot
Activate DISTRONIC Distance-Pilot and drive off automatically
The following options are available for activating DISTRONIC Distance-Pilot:
- Using the cruise control resume switch, call up the last selected set speed (set speed v > 20 km/h).
The brake pedal must be actuated to activate in standstill.
- To drive off from a standstill, actuate the accelerator pedal shortly, or use the cruise control resume switch.
The vehicle moves off and adapts its speed to the maximum speed of the vehicle immediately ahead up to the selected target speed. If there is no vehicle immediately ahead, the DISTRONIC Distance-Pilot functions like the CC.
For vehicles at a standstill a specified distance limit exists beyond which a stationary vehicle is no longer displayed.
Automatic distance control
If the vehicle driving immediately ahead brakes or accelerates, the DISTRONIC Distance-Pilot can initiate the following measures for deceleration or acceleration of the vehicle:
- Increase/reduce engine torque.
- Increase/reduce braking torque.
The brake application takes place by means of hydraulic pressure controlling in the wheel brake cylinder by the traction system hydraulic unit according to the current vehicle status. To do this the Electronic Stability Program control unit assesses various variables such as the required braking torque.
The driver must press on the brake pedal if he sees that the instigated measures are not adequate to avoid a possible collision.
If the driver does not intervene, an additional intervention by the brake system is made by the Brake Assist.
If the vehicle driving immediately ahead accelerates again, the engine torque is increased and the vehicle also accelerates. The increase in engine torque is dependent on the ascent or the descent involved, among other things.
The maximum (positive) acceleration is dependent on the selected transmission mode. The driver can influence the vehicle's acceleration behavior by selecting the transmission mode using the transmission mode button.
The driver furthermore has the option of operating the accelerator pedal to accelerate the vehicle (e.g. when overtaking). As soon as the driver actuates the accelerator pedal, no distance control occurs. The IC shows the "DISTRONIC passive" message. If the automatic distance control requires greater acceleration than the driver is providing, the driver request is overlaid by the request for automatic distance control and the "DISTRONIC passive" message disappears.
Speed control
If the vehicle is in active distance control and the vehicle driving immediately ahead accelerates above v = 210 km/h or removes itself from the detection area of the radar sensor system, the automatic distance control switches over into the automatic speed control.
Going back into a lane/person in the front regulation
If the vehicle driving immediately ahead turns off and there is another vehicle in front, the system only switches over to the new target vehicle if it is moving. The system does not operate for stationary objects unless a preceding vehicle is tracked to a standstill. If while driving a vehicle turns in front within the safe distance to the vehicle driving immediately ahead, the distance to this new vehicle is regulated. If the vehicle is in speed control and a vehicle turns onto the lane driven in this vehicle is registered as the vehicle driving immediately ahead. If the distance to the swinging-in vehicle lies below the value that was preselected, Distance Pilot DISTRONIC decelerates the vehicle. If the requested brake power is not sufficient, a visual and acoustic warning is issued and the driver must press the brake pedal. If the driver fails to respond, the Brake Assist initially initiates (in addition to the visual and acoustic warnings) an automated partial and then maximum full-stop braking.
The negative acceleration (deceleration) is limited to 50 % (approx. a = 5.0 m/s2) of the max. possible braking power. The DISTRONIC Distance-Pilot will be deactivated in the process. The driver is notified of this by the sounding of an intermittent tone over the instrument cluster speaker and a warning indicator in the instrument cluster's multifunction display. The driver can activate the DISTRONIC Distance-Pilot controller unit again.
Automated Stop Vehicle
With an activated DISTRONIC Distance Pilot, the vehicle will follow the vehicle driving in front to a standstill. The deceleration here is due to the service brake. The service brake also secures a stationary vehicle against rolling away.
After a defined time period the electric parking brake is also activated (standstill control safety strategy).
Securing the vehicle using the DISTRONIC Distance-Pilot (standstill control) does not replace securing the vehicle for parking.
Limits of the DISTRONIC Distance-Pilot
The traffic situations described below show the limits of the DISTRONIC distance pilot.
Obstacles and stationary vehicles
The DISTRONIC Distance-Pilot does not brake for obstacles or stationary vehicles which were not previously registered as the target object. If, for example, the detected vehicle turns off and there is an obstacle or stationary vehicles behind it, no automatic intervention by the brake system occurs.
Curves, curved entrances and exits
The DISTRONIC Distance-Pilot can only provides limited detection of vehicles in curves. One's own vehicle can then brake unexpectedly or late.
Vehicles moving across in front of one's own vehicle
The DISTRONIC Distance-Pilot may detect vehicles in cross traffic by mistake. For an activated distance control the vehicle can start off unintended, (e.g. at a traffic light with cross-traffic).
Offset driving style
The DISTRONIC Distance-Pilot may not be able to detect vehicles driving offset to one side. The distance to the vehicle in front becomes too small.
Lane change by other vehicles
The DISTRONIC Distance-Pilot does not yet detect the vehicle moving into the lane. The distance to the vehicle moving into the lane becomes too small.
Narrow vehicles
The DISTRONIC Distance-Pilot does not detect the vehicle in front at the edge of the carriageway because of its narrow width. The distance to the vehicle in front becomes too small.
| Electrical function schematic for DISTRONIC Distance-Pilot | PE30.30-P-2068-97ZGA | ||
| Overview of system components for driver assistance systems | Model 463 (except 463.342) as of model year 2019 with code EM4 (Driving Assistance package) | GF54.00-P-9998GWM |