U.S. safety regulators are investigating complaints that automatic braking in Jeep Grand Cherokees can come on for no reason.
The National Highway Traffic Safety Administration says the probe covers about 20,000 of the SUVs from the 2014 model year.
The agency says it has nine complaints that the autonomous brakes suddenly reduced the Jeeps' speed for no apparent reason.
The Grand Cherokee and other vehicles have cruise control systems that use radar and cameras to detect objects and automatically brake to avoid a crash. The systems are among the first steps toward cars that drive themselves.
Many people who complained said the mysterious braking nearly caused other cars to hit them from behind.
The agency will investigate how often the problem happens. The probe could lead to a recall.
