GF30.30-P-3400LE Plus Light Intelligent Cruise Control, Function

GF30.30-P-3400LE Plus Light Intelligent Cruise Control, Function
- with CODE (239) Autonomous intelligent cruise control Plus Light
- as of model year 2010

Component Identification:

Function requirements for Autonomous intelligent cruise control Plus Light, general
^ "Circuit 61 ON" (engine running)
^ Autonomous intelligent cruise control Plus Light coded in central gateway control unit (N93)
^ Soiling and function test of the DTR radar sensor (A89b1) completed successfully
^ Electronic Stability Program (ESP) not deactivated
^ No ESP control intervention function
^ Parking brake not applied
^ Gear range "D" engaged
^ Brake pedal not actuated
^ CC pushbutton (S40/4) in autonomous intelligent cruise control position
(LIM indicator lamp (LIMITER) off)

Plus Light intelligent cruise control, general
The intelligent cruise control regulates the speed and the distance to the vehicle ahead according to the driver's specifications (target speed and required distance) in the range of 0 to 200 km/h.

In doing so the autonomous intelligent cruise control regulates the set target speed in an empty lane (no vehicle moving ahead) as per 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 engine power
- Activating the brakes
- Changing gear (downshift)

If the traffic situation allows an increase in speed as the vehicle immediately ahead has accelerated or left the lane, for example, the autonomous intelligent cruise control increases the speed back up to the set target speed.
In curves adaptation of the speed takes place on comfort grounds dependent on a maximum permissible lateral acceleration in the curve. If the target destination gets lost in the curve, the speed is held until the cornering ends or the target destination is recognized again.

The signals from the CC push button switch are detected by the steering column tube module (N80) and transmitted to the radar sensors control unit (SGR) (N62/1) via the chassis CAN (CAN E).

The instrument cluster (A1) sends the selected maximum speed via the chassis CAN and central CAN (CAN F) to the radar sensors control unit.

The radar sensors control unit actuates displays in the instrument cluster and warning tones.

The DTR control unit (A89n1) actuates the DTR radar sensor (A89b1), evaluates the sensor data from the DTR radar sensor and transfers the data over the dynamics CAN (CAN H) to the radar sensors control unit.
After evaluating all the sensor data and input signals, the radar sensors control unit assumes full control of the vehicle in the longitudinal direction by transmitting signals for acceleration, deceleration, braking and gear changing to the respective control units via the chassis CAN.

The requests to accelerate or decelerate are transmitted via the chassis CAN to the CDI control unit (N3/9) (for diesel engines) or to the ME-SFI [ME] control unit (N3/10) (for gasoline engines). A braking request is transmitted to the ESP control unit (N47-5) via the vehicle dynamics CAN.
A switching request at the automatic transmission is transmitted via the chassis CAN and drive train CAN (CAN C) to the ETC control unit (N15/3) (for transmission 722.6) or to the electric controller unit (VGS) (Y3/8) (for transmission 722.9).

Plus Light intelligent cruise control, function sequence
The function sequence is described in the following points:
^ Soiling and function test function sequence
^ Automatic acceleration function sequence
^ Automatic braking function sequence
^ Activating Plus Light intelligent cruise control
^ Specified speed function sequence
^ Function sequence for specified distance
^ Special driving situations function sequence
^ Function sequence for stopping behind target vehicle
^ Function sequence for deactivating intelligent cruise control

Soiling and function test function sequence
The DTR control unit performs a soiling and function test of the radar sensor to ensure smooth functioning of the radar system after each engine start. The intelligent cruise control cannot be activated if a malfunction is established or if there are no objects (for the function test) in the detection range of the radar sensor.

The message "Intelligent cruise control currently unavailable" appears in the multifunction display (A1p13) of the instrument cluster.

Automatic acceleration function sequence
For reasons of safety and comfort, the automatic acceleration of the intelligent cruise control is limited to about 2.5 m/s 2.

Automatic braking function sequence
Intervention by the brake system is limited to 40% (about 4 m/s 2 ) of the maximum possible braking power for reasons of safety and comfort. Driving situations that require more than 40 % braking power are signaled by the driver optically by the DTR indicator lamp (A1e59) in the instrument cluster and acoustically by an intermittent warning tone.
This interval warning tone requires the driver to observe the traffic situation and to intervene himself if necessary The intermittent warning tone is turned off automatically when the situation becomes less critical and cannot be deactivated manually.

Activating Plus Light intelligent cruise control
The intelligent cruise control can be activated at any speed from > 0 to 260 km/h. However, at speeds <30 km/h, it can only be activated if a preceding vehicle is detected.

By pulling the CC [TPM] switch, the intelligent cruise control is activated with the last saved target speed provided that a target speed has already been saved since the last engine start (set). If no specified speed has been stored, the intelligent cruise control sets the current vehicle speed as the specified speed.

By moving the CC [TPM] switch up or down, the intelligent cruise control is activated with the current vehicle speed as the target speed.

The message "Distronic PLUS Unavailable" appears if:
- The radar plate in the radiator grille is dirty or iced up
- Radar operation is not possible due to weather conditions
- Transmission/reception signals are limited by external factors (e.g. electromagnetic interference)
- Radar system is outside the operating temperature
- On-board voltage is too low

A warning tone is also sounded in addition to the message.

Component Identification:

When the intelligent cruise control 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 immediately ahead is shown in the multifunction display of the instrument cluster with the current distance from it in meters. The orange triangle at the top of the segment ring indicates the set target speed.

If there is no vehicle immediately ahead detected with intelligent cruise control activated then no segments in the speedometer are lit up.

Specified speed function sequence
The CC [TPM] switch can be moved up or down to different degrees to increase or reduce the specified speed in 1 km/h or 10 km/h increments (two settings).

The minimum target speed that can be set is 30 km/h and the maximum target speed 200 km/h.

If the intelligent cruise control is activated at a speed of <30 km/h, the maximum speed is automatically set to 30 km/h. If the intelligent cruise control is activated at a speed between 200 and 260 km/h, the specified speed is set automatically to the maximum permissible specified speed of 200 km/h.

Function sequence for specified distance
With the DTR distance potentiometer (N72r1), the specified distance from the vehicle in front can be set in six steps between about 1.0 and 2.0 s, depending on vehicle speed. This corresponds, in the 3rd stage, at a speed of approx. 100 km/h, a nominal distance of approx. 42 m. The nominal distance is converted from seconds to meters depending on the speed of the driver's own vehicle and indicated as a white line in the multifuntcion display 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.

Component Identification:

If the set target speed to the vehicle ahead falls short, the intelligent cruise control 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 intermittent warning tone signals the driver to carefully observe the driving situation and to intervene himself by measured heavy braking or steering as necessary.

Special driving situations function sequence
- If the driver accelerates on his own initiative faster than the acceleration defined by the intelligent cruise control, the intelligent cruise control does not shut down, but changes to the passive state. The message "Distronic PLUS passive" appears on the multifunction display of the instrument cluster, and in this case no distance control from the vehicle in front takes place. When the driver releases the accelerator pedal again (vehicle speed drops), the intelligent cruise control resets to the set target speed and distance control is once again activated.
- The system does not operate for stationary targets (objects) 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, during the journey, the vehicle ahead pulls out of the lane and another vehicle is now moving ahead of the host vehicle, then the system will only control the distance to this new vehicle if it is moving. In the event that a stationary obstruction is encountered, an intermittent warning tone and the DTR warning lamp warn the driver of an impending collision.
- If the preceding vehicle leaves the same lane at a speed <30km/h, the intelligent cruise control is deactivated and a deactivation tone sounds.

Function sequence for stopping behind target vehicle
In a situation where the target vehicle stops, regulation continues up to a standstill and is then switched off. The driver is informed through fading out of the segment ring in the speedometer and a subsequently sounding switching off tone through the intelligent cruise control switching off. The set braking torque at the point in time of switching off is slowly reduced after the switching off tone.

The intelligent cruise control is already deactivated in the following situations before reaching a standstill:
- Loss of the target vehicle at a speed of <25 km/h
- For slopes >4% the intelligent cruise control C is turned off dependent on the slope for a higher speed (e.g. a 4% slope at 7 km/h and a 30% slope at 25 km/h)

Function sequence for deactivating intelligent cruise control
The intelligent cruise control mode is deactivated if:
- The CC [TPM] switch is pushed forwards
- By pressing the CC [TPM] switch, a switchover to the Variable Speed Limiter takes place (LIM indicator lamp lights up)
- The brake pedal is operated.
- Parking brake is actuated
- ESP operates
- ESP switched off
- ESP deactivated (a fault)
- Gear range "N" or "R" engaged
- A vehicle in front moving at a speed of <25 km/h is no longer detected (lost)
- Radar function no longer available
- Ignition is switched off (circuit 15 OFF)