This advanced, radar-based cruise control monitors the vehicle ahead and adjusts your speed to help maintain a chosen following distance. It can even bring the car to a halt if it senses stopped traffic, then resume automatically. Should the car ahead slow to a stop, the PRE-SAFE Brake system can automatically engage up to 40% of available braking power and issue an audiovisual alarm. If you still haven't applied the brakes within 0.6 seconds of a calculated impact, it automatically engages 100% braking power.