DISTRONIC PLUS, function - GF30.30-P-3300SX
ENGINE 156, 273, 275 in MODEL 216 with CODE (233) Distronic Plus up to Model Year 8
ENGINE 156, 272, 273, 275, 642, 629 in MODEL 221 with CODE (233) Distronic Plus up to Model Year 8
Detection of a weaving vehicle with DISTRONIC PLUS activated
The Distronic Plus regulates, the speed and the distance to the vehicle traveling immediately ahead according to the request from the driver (specified speed and distance), in the range from 0 km/h to 200 km/h.
If the lane ahead of the vehicle is clear, DISTRONIC PLUS regulates the set target speed in the same way as a conventional cruise control. As the car approaches a preceding vehicle, the speed is reduced in order to maintain the target distance set by the driver by:
- Reducing the engine output
- Activating the brakes
- Shifting the gears
If the traffic situation allows the speed to be increased, e.g. because the preceding vehicle accelerates or leaves the lane, DISTRONIC PLUS increases the speed back to the set target speed.
Function requirements
- "Circuit 61 ON" (engine running)
- "ADTR_AVL" (DISTRONIC PLUS) coded in central gateway control unit (N93)
- Radar sensor system not disabled
- Dirt/function test of the long range radar completed successfully
- ESP not deactivated
- Driver door closed and driver seat belt plugged in
- Parking brake not applied
- DIRECT SELECT gear selector switch (S16/13) in "D" position
- Pressing the Cruise control switch (S40/4 or S40 for) causes the system to switch to DISTRONIC PLUS (LIM indicator lamp Off)
Above approx. 30 km/h the functionality of DISTRONIC PLUS is the same as that of the conventional DISTRONIC.
The DTR control unit (A89n1) evaluates sensor data from the long range radar and transmits data via the vehicle dynamics CAN to the radar sensors control unit (SGR) (N62/1).
Sensor data from the short range radar is evaluated via two sensor CANs by the radar sensors control unit.
The radar sensors control unit then fuses the data representing identical objects from the long and short range radar. Following analysis of all sensor data and input signals, the radar sensors control unit takes over full longitudinal control of the vehicle by sending signals via the vehicle CAN to the ESP control unit (N47-5) to accelerate, brake or shift gear. The ESP control unit evaluates these signals and actuates the respective control units (e.g. for switching) via the chassis CAN.
The radar sensors control unit also actuates warning tones and display in the instrument cluster (A1) and on the headliner.
Automatic acceleration
The automatic maximum acceleration of DISTRONIC PLUS is limited to approx. 2.5 m/s2 for reasons of safety and comfort.
Automatic braking
Intervention by the brake system is restricted to 40% (approx. 4 m/s2 ) of the maximum possible deceleration capacity for reasons of safety and comfort. Driving situations requiring more than 40 % braking power are indicated to the driver visually by the DTR warning lamp (A1e59) in the instrument cluster and acoustically by a tone. This tone is an intermittent chime which advises the driver to observe the traffic situation and intervene if necessary (take over control). The tone is shut off automatically when the situation becomes less critical; it cannot be deactivated manually.
Dirt/function test
In order to guarantee proper functioning, the long range radar carries out a dirt/function test after every engine start. If a malfunction is established or no objects (for the function test) are available in the long range radar detection range, DISTRONIC PLUS cannot be activated and the message "DISTRONIC PLUS not available" appears in the multifunction display (A1p13) of the instrument cluster.
Activation
Pulling the CC [TPM] switch activates DISTRONIC PLUS with the most recently stored target speed, providing a target speed has actually be set since the last engine start. If there is no stored target speed, DISTRONIC PLUS sets the current vehicle speed as the target speed.
DISTRONIC PLUS can be activated from a standstill up to a speed of 200 km/h. However, at speeds <30 km/h it can only be activated if a preceding vehicle is detected.
When a preceding vehicle is detected, it can be observed in the instrument cluster with its current speed and distance.
When stationary, DISTRONIC PLUS can only be activated if it can detect another stationary vehicle at a distance <6 m in front of it. To simplify activation when at a standstill, the driver can depress the brake pedal when activating DISTRONIC PLUS.
The message "DISTRONIC PLUS unavailable" is also shown, if:
- Radar sensor system is disabled
- The radar plate in the radiator grille is dirty or iced up
- Operation is not possible because of the weather
- Transmission/reception signals are limited by external influence (e.g. electromagnetic compatibility interference)
DISTRONIC PLUS activated
The orange triangle at the top of the segment ring indicates the set target speed. When DISTRONIC PLUS is activated, the segments between the measured speed of the vehicle moving ahead and the set target speed are illuminated in the electronic speedometer (A1p8) in the instrument cluster.
The vehicle ahead is shown with the actual distance in meters.
For vehicles with "Night View Assist" the distance graphic in the multifunction display is not displayed for an activated Night View function!
Target speed
The CC [TPM] switch can be moved up or down to increase or reduce the target speed in 1 km/h or 10 km/h increments (two settings).
The minimum target speed that can be set is 30 km/h, while the maximum settable target speed is 200 km/h.
If DISTRONIC PLUS is activated at a speed of <30 km/h the nominal speed will automatically set to 30 km/h. If DISTRONIC PLUS is activated at a speed between 200 km/h and 260 km/h, the target speed is automatically set to the maximum permissible target speed of 200 km/h.
Target distance
Using the DTR distance potentiometer (S40r1, S40/4r1), which is integrated in the CC [TPM] switch, the target distance to the vehicle ahead can be set in six increments between approx. 1.0 s and 2.0 s depending on the speed.
In the third stage at a speed of 100 km/h, this corresponds to a target distance of around 42 m.
The target distance is converted from seconds to meters depending on the speed of the host vehicle and is displayed in the form of a white line on the range indicator in the instrument cluster.
The target distance in the distance indicator matches the current vehicle speed without the driver having to adjust the DTR distance potentiometer.
The legally required minimum distance is thus always guaranteed in the setting range for the target distance.
Target distance falls short
If the preceding vehicle comes within the set target distance, DISTRONIC PLUS reduces the speed.
In driving situations requiring more than 40 % braking power (dangerous situations), the DTR warning lamp in the instrument cluster lights up and the takeover tone signals to the driver to carefully observe driving situation and to intervene himself by measured heavy braking or steering if necessary.
Special driving situations
- If the driver accelerates on his own initiative faster than the acceleration defined by DISTRONIC PLUS, then DISTRONIC PLUS does not shut down, but changes to the passive state. In the multifunction display of the instrument cluster, the message "DISTRONIC PLUS passive" appears and distance control from the vehicle ahead does not take place for this acceleration procedure.
If the driver once more releases the accelerator (vehicle speed decreases), DISTRONIC PLUS once again regulates the set target speed and distance control is reactivated.
- The system does not operate for stationary targets (e.g. vehicles) unless a preceding vehicle is tracked to a standstill.
- If a vehicle cuts in between the host vehicle and the vehicle ahead (target vehicle), the system switches over to the new target vehicle.
- If the preceding vehicle turns off and there is another vehicle in front, the system only switches over to the new target vehicle if it is moving. In the event that a stationary obstruction is encountered, an intermittent takeover tone and the DTR warning lamp warn the driver about the impending collision.
- If the preceding vehicle leaves the same lane at a speed <30 km/h, DISTRONIC PLUS is deactivated and a deactivation tone sounds.
Stop & Go traffic (traffic jam)
Automatic driving off (for stop & go traffic)
DISTRONIC PLUS-controlled start-off in stop & go traffic occurs only after the driver has acknowledged it by pulling the CC [TPM] switch or by briefly operating the accelerator pedal.
To facilitate operation of the system, the driver can depress the brake pedal while stationary without deactivating DISTRONIC PLUS. However, the driver must release the brake pedal in order to command start-off under DISTRONIC PLUS control.
Deactivation
DISTRONIC PLUS is deactivated if:
- The CC [TPM] switch is pushed forwards
- The brake pedal is depressed (except when stationary)
- The driver switches to Variable Speed Limiter by pressing the CC [TPM] switch (LIM indicator lamp on) (except)
- DIRECT SELECT gear selector switch in position "N"
- A preceding vehicle moving at a speed of <30 km/h is no longer detected (lost)
- Function requirements for DISTRONIC PLUS cease to apply
| Component description for the CC [TPM] switch | S40/4 Except code 494 USA version |
GF30.20-P-2100SX | |
| S40 With code 494 USA version |
GF30.20-P-2100TX | ||
| Component description for the DTR controller unit | A89 | GF30.30-P-3210SX | |
| Component description for radar sensors control unit | N62/1 | GF30.30-P-3301SX | |
| Component description for the bumper radar sensors | A86/1b1-4, A86/2b1-4 | GF30.30-P-3302SX |