Adaptive Cruise Control (ACC) is a system added to many vehicles that uses radar waves to control the speed of the vehicle while in traffic. The cruise control we are all familiar with simply sets the vehicle’s speed to a certain level and then maintains that level until the driver interrupts either by disengaging a switch or applying the brake. The new ACC systems use radar waves and cameras to determine the speed of the traffic around you and adjust the speed accordingly.

For all of you who have driven in traffic with someone who crawls next to your bumper or takes forever to pass the car ahead because of their reluctance to disengage their cruise control it seems clear that the adaptive technology will be the wave of the future. Currently the number of these systems out there is limited and some are more sophisticated than others.

Adaptive cruise controls seem to be divided into two major types: the fully braking systems that will completely stop the vehicle if necessary; and the others that will slow and accelerate as needed while following vehicles at various speeds.

The full stop system is truly a combination of ACC and a collision warning or prevention system. It is a highly technical system that is a major value add-on. The ACC system that only slows or speeds up the vehicle in traffic is simpler and used in less expensive vehicles.

So what does this have to do with automotive glass? Well, in most cases, nothing. Most systems use a radar transmitter and receiver located in the grill or front bumper. However, there are some systems that utilize a dual system of bumper mounted and windshield mounted sensors that control the vehicle front-to-back (ACC) and side-to-side (lane departure). These systems will require dealer calibration if the windshield or sensor is replaced or displaced. The Volvo and Audi systems are two examples that utilize the through windshield sensor for their ACC systems.

Here are a few YouTube videos that illustrate the differences:

http://www.youtube.com/watch?v=tVkVz79fgnY

http://www.youtube.com/watch?v=yTrsvrReupM

When replacing the windshield in some of these highly sophisticated vehicles make sure that you are aware of the systems built into the vehicle and the processes necessary to restore it to a safe operating condition before beginning any work.