- Fig. 1 Top of centre console: Button for downhill assist function
- Fig. 2 Display: Downhill assist function
The downhill assist function helps you to drive down steep gradients at a constant speed.
To switch on the downhill assist function, press the button 
in the centre console Fig. 1 or next to the selector gate. The diode in the button will light up.
in the centre console Fig. 1 or next to the selector gate. The diode in the button will light up.Press the button again to switch off the downhill assist function. The diode in the button will go out.
The downhill assist function limits the speed when driving forwards or reversing on steep gradients by automatically braking all four wheels. The anti-lock brake system remains activated so the wheels are prevented from locking up. On vehicles with manual gearbox, the downhill assist function adapts the engine's speed so that it does not drop below the idling speed of the engine.
When the downhill assist function is switched on, it maintains the current speed when you start a descent. The system can only be switched on when driving below approx. 60 km/h. On vehicles with manual gearbox, the driving speed is controlled to between 9 and 30 km/h. On vehicles with automatic gearbox, the speed range is from 4 to 30 km/h. You can increase or reduce the speed within this range anytime by pressing the accelerator or brake pedal. The system also makes the vehicle easier to steer by optimising the brake force distribution.
However, the surface must have enough grip for the downhill assist function to function properly. It will not function properly if, for example, you are driving down a hill with an icy or slippery surface WARNING!.
The system will not control the driving speed when you are driving between approx. 30 and 60 km/h. The system is then in standby mode which is indicated by the lit diode in the button. The system is automatically switched off and the diode goes out once the speed exceeds 60 km/h.
The instrument cluster display indicates whenever the driving speed is being actively controlled to a certain speed up to approx. 30 km/h Fig. 2. Two dashes "--" will appear when the system goes into standby mode.
The downhill assist function is activated automatically if the following conditions are met:
- The diode in the button must be lit up.
- The driving speed must be lower than approx. 30 km/h.
- The gradient must be approx. 10%.
- It is essential that you adjust your speed to suit the weather, road and traffic conditions. Do not let the extra safety provided tempt you into taking any risks when driving - this can cause accidents.
- The downhill assist function is not able to overcome the physical limits of adhesion. Therefore it is important that you always drive at a safe speed for the prevailing conditions and traffic situation.
- The downhill assist function cannot keep your vehicle's speed constant under all circumstances when you are driving down a hill (e.g. if the road is slippery) and cannot replace the full concentration of the driver.