Available as an option, this cruise control function regulates your speed according to the distance between your vehicle and the vehicle in front. A radar sensor monitors the road ahead up to a distance of 200 m. If you have set a cruising speed but have begun to gain on the vehicle in front because it is driving more slowly, this is detected by the radar sensor.
The system now reduces the speed of your vehicle at a maximum rate of 3.5 m/sec2 by restricting the throttle or gently applying the brakes, until the distance that you have preset is maintained. Your vehicle will now continue at a reduced speed. If the other vehicle decelerates further, adaptive cruise control will continue to reduce your cruising speed – even down to a halt.
For additional safety, if the system detects that the distance from the vehicle in front is decreasing, it will also prepare your vehicle for braking by precharging the braking system so that the brake pads are already in light contact with the brake discs. However, drivers still have to perform heavier braking themselves.
As soon as the road ahead clears again, your vehicle will accelerate back up to the cruising speed originally set.
If your vehicle approaches the vehicle in front too quickly, Porsche Active Safe (PAS) will issue audible and visual warnings. In addition, the system briefly jerks the brakes and if necessary initiates target braking, with any braking pressure applied by the driver being increased within certain system limits.
* Available from November 2012 at the earliest.