Cadillac Debuts Front/Rear Automatic Braking

General Motors Co.'s Cadillac unit is offering front and rear automatic low-speed braking on its 2013 ATS sport sedan, SRX crossover and XTS large sedan.

The system uses radar, ultrasonic sensors and vision systems to determine if an impact is imminent. The option is intended to avoid collisions in parking lots and in stop-and-go traffic.

When the technology senses an impending crash, it alerts the driver but applies the brakes if no action is taken. When the vehicle stops, the system activates the electric parking brake, releasing it when the driver presses on the accelerator.

Cadillac engineers say they spent eight years analyzing driver behavior so they could tweak the system to avoid unintended activation. The driver can override the system, which the company describes as a last-resort safety feature.