Audi A4 Owners Manual
System limitationsControls / Adaptive cruise control (ACC) / System limitations
General notes
The following situations could impair the function of the radar sensor.
The adaptive cruise control is subject to given physical limits and also has certain limits determined by the system itself. Under certain circumstances the driver may feel that the ACC system is responding unexpectedly or belatedly. For this reason, please always give your full attention to road traffic and if necessary take action yourself:
- • When driving through bends.
- • When vehicles in front are not in line with your vehicle.
- • When other vehicles change lanes.
- • When other vehicles are not clearly discernible
- • When vehicles are stationary.
WARNING
The radar sensor's "field of vision" can be impaired by rain, snow or a lot of water on the road. This results in vehicles in front not being properly recognised or, in some circumstances, not being detected at all. If necessary, take action yourself!
When driving through bends
Driving into a bend
Driving out of a bend
Driving into a bend
When you are driving into a bend, the ACC system may react to a vehicle travelling in the other lane and therefore brake the vehicle, fig. 149. You can override the braking effect by pressing the accelerator.
Driving out of a bend
When you are driving out of a long bend, the ACC system may - in the course of its calculation of the lane ahead - react to a vehicle travelling in the other lane and therefore brake the vehicle, fig. 150. You can override the braking effect by pressing the accelerator.
Vehicles in front travelling out of line
The vehicle in front is outside the range of the radar sensor
Vehicles in front which are not in line with your vehicle cannot be detected by the ACC system until they are within the range of the sensor.
Other vehicles changing lanes
A vehicle is changing lanes
Vehicles which are very close to you when they move onto your lane cannot be detected by the radar sensor until they move into its range.
Not clearly discernible vehicles
Motorcycle in front
Vehicles that are not clearly discernible, e.g. a motorcycle travelling in front of you and vehicles with a large amount of ground clearance or protruding freight, are often identified late or may not be detected at all.
Stationary vehicles
Vehicle turning off and vehicle stationary
Vehicle changing lane and vehicle stationary
If a vehicle detected by the ACC system turns off or changes lane and another stationary vehicle is located in front of that vehicle, the ACC system will not react to the stationary vehicle ⇒ fig. 154 and ⇒ fig. 155.
