New Defect Investigation Over GM’s Impala Braking System

U.S. regulators are investigating whether a General Motors Co. car’s automatic-braking system kicked in unexpectedly at 40 miles per hour, causing a crash.

A 2014 Chevrolet Impala owner said his car’s driver-assist system turned on and forced a complete stop with “full braking force,” the National Highway Traffic Safety Administration said in announcing the investigation on its website yesterday.

Unlike the Chevrolet Cobalt, which was recalled for a flawed ignition switch and is no longer sold, the Impala represents the “new GM” that emerged in 2009 after a government-backed bankruptcy. Chevrolet’s third-best selling model in the U.S., the full-size sedan was redesigned for 2014. It received the highest sedan rating from Consumer Reports magazine – the first time in 20 years a U.S.-made car outscored Japanese or European-made counterparts for the honor.

The largest U.S. automaker is cooperating with the agency’s investigation, said Alan Adler, a company spokesman.

The Impala owner experienced multiple events at different locations and in various road conditions, the agency said. In one incident, traveling at 40 miles (64 kilometers) per hour with no traffic directly ahead, the forward-collision avoidance system beeped three or four times. The brakes fired and stopped the car, resulting in another vehicle crashing into it from behind. No one was hurt.

The automatic-braking system is one of a suite of “crash avoidance” technologies that automakers and regulators are counting on to reduce the more than 30,000 fatalities that occur on U.S. highways each year. The systems are also a key component of self-driving cars like the one in development by Google Inc.

Vehicle-to-vehicle communications, which NHTSA says may one day save as many lives as seat-belts, also rely on the ability of cars to talk to each other and react to crash situations more quickly than their human drivers.

The agency is beginning the defect probe based on the single complaint. The investigation affects an estimated 60,580 cars and will be assessing the frequency, scope and consequences of the alleged defect.

The Impala was one of the 18 new or refreshed GM vehicles arriving in the U.S. last year, among the largest waves of new products in the company’s history. GM officials were attempting to transform the company’s lineup into one of the newest in the industry from one of the oldest.