Adaptive Cruise Control (ACC)
Adaptive cruise control (ACC) is a driver-assistance function that automatically adjusts vehicle speed to help maintain a selected following gap from a vehicle ahead.
What ACC does
The driver normally selects a cruising speed and following-gap setting. Using sensors such as radar and cameras, the system can reduce acceleration, coast, or apply braking when it detects slower traffic, then accelerate toward the selected speed when the path clears. Exact low-speed, stop-and-go, and restart behaviour varies by vehicle.
ACC differs from conventional cruise control, which generally holds a selected speed without responding to traffic ahead. ACC also does not by itself steer the vehicle; lane-centering or steering support is a separate function even when both are combined in one assistance package.
The system has operating limits. Sensor blockage, severe weather, sharp curves, cut-in vehicles, stationary objects, unusual road users, or situations outside the approved speed range can reduce or prevent a correct response. Capability and warnings differ between vehicles, so the owner’s manual defines the applicable conditions.
ACC is not autonomous driving. The driver remains responsible for monitoring traffic, keeping control, and braking or steering when needed.
For system architecture, variants, and limitations, see Adaptive Cruise Control.