Driver responsibility when using adaptive cruise control
A main limitation of adaptive cruise control that you need to be aware of relates to driver responsibility. When using the function, you are still required to actively and attentively drive the car. You are responsible for all decision-making, actions and responses that are part of driving.
Adaptive cruise control does not know your intentions or the intentions of other drivers. It cannot predict or identify every potentially hazardous situation that an attentive driver can. It's your responsibility to continuously assess adaptive cruise control's performance and act if necessary. As long as you judge its input to be correct, you can let it guide your driving.
Important
Driving conditions
Assessing adaptive cruise control's performance requires that you take all driving, traffic, weather or road conditions into consideration. For example, if there is poor visibility you may need to increase the distance to vehicles ahead compared to the distance kept by adaptive cruise control. The same applies to maintaining a speed that is safe for the current road and traffic conditions.
Improved safety and convenience
When used correctly, adaptive cruise control can improve safety and reduce the effort of driving. In some cases, it can compensate for driver errors, such as mistakes caused by lapses of attention or distractions. This potential benefit is a supplement to safe driving practices. It does not reduce or replace the need for the driver to stay attentive and focused on driving safely.
Driver readiness
Using speed- and distance-keeping features can result in long periods of you not using the pedals. However, you must remain prepared and ready to brake or accelerate manually if necessary. Avoid changing your driving posture in ways that can delay your response time.
Speed range for adaptive cruise control
- When using adaptive cruise control, you can set target speeds between 30-150 km/h (20-90 mph).
- When following another vehicle, adaptive cruise control can stay active below 30 km/h (20 mph).
- In situations where you are driving slowly behind other vehicles, such as in a traffic queue, you may be able to activate adaptive cruise control despite driving slower than 30 km/h (20 mph). This requires a vehicle ahead whose speed your car can match.1
Activation and availability
Several conditions must be met to activate adaptive cruise control. They can be related to the current traffic and road conditions or the car's system status. Some are related to the car being driving-ready, such as the driver wearing their seatbelt and all doors being closed. Others relate to your current driving situation, such as driving at a speed within the speed range for adaptive cruise control. If activation is prevented, the specific reason is typically communicated in the driver information area.
Keeping track of vehicles ahead
One of adaptive cruise control's capabilities is to adapt the car's speed to a vehicle ahead and maintain a certain distance to it. Adaptive cruise control's behaviour and ability to track traffic ahead depends on several factors, such as your speed and the speed of the vehicle in front.
- If adaptive cruise control follows a vehicle that comes to a stop, Pilot Assist slows your car down to a stop behind the other vehicle.
- If a stopped vehicle is detected ahead of you, adaptive cruise control will slow your car down in an attempt to stop behind the other vehicle.
- Depending on your driving speed, the car may not be able to reach a full stop behind the vehicle in front. You are always responsible for keeping track of the surrounding traffic and driving the car in a way that allows you to react and control it safely.
- When driving at high speeds, stationary vehicles in front of you can be misinterpreted by adaptive cruise control, such as when catching up to a stationary traffic queue. In a situation like this, adaptive cruise control will not consider the stopped cars or slow your car down. Always be attentive and available to control your car and brake when necessary.
Warning
Stopped or slow vehicles ahead
A stopped vehicle in your lane is a collision risk that requires you to act by braking or steering.2
- At low speeds, adaptive cruise control may pause when following another vehicle if:
- there is uncertainty whether what's detected in front is a stopped vehicle or another object3.
- the vehicle ahead makes a turn and leaves your driving path.
- you manually steer the car out of your current lane.
Car status and systems
Adaptive cruise control relies on the accurate detection and identification of surrounding traffic and road conditions. This includes using information from cameras, radars and other sensors. The detection system cannot handle all driving, traffic, weather or road conditions. Read the separate manual sections about detection types, how they work and their limitations to better understand how adaptive cruise control's performance can be affected.
- To adapt the speed to vehicles ahead, the car uses a combination of radar and camera detection. Consequently, conditions and limitations of these systems can affect the availability and performance of this feature.
- When adaptive cruise control's set speed is set to adapt to the speed limit, the value is provided by the car's road sign information system. In some conditions, it may not be able to provide an accurate speed limit.
Important
Car faults
Certain car faults can affect the availability of driver support features. Check the car status view for indicated issues if adaptive cruise control is unavailable.
Car alterations
Modifications, repairs and accessory installations can negatively affect or limit driver support features. There is a separate manual section with detailed information on this topic.
Adaptive cruise control is unavailable when a towbar is mounted and connected to your car.