Advanced driver assistance systems, which include lane-keeping, adaptive cruise control and automatic braking, are designed to make cars and driving safer than ever. But sometimes, functions like automatic braking malfunction and have the opposite effect, wrecking a driver’s confidence in driving at all.

Ideally, automatic braking helps slow down or stop the car when the system detects a risk in order to avoid a collision, especially if the driver doesn’t react quickly enough.

Apparently, though, the cars occasionally brake themselves even when there is no risk present, reports the . It notes the National Highway Traffic Safety Administration has received over 400 individual complaints over the past three years from Nissan, Honda, Volkswagen and other automakers over automatic braking issues.

Most of the complaints are from drivers who said their car’s brakes activated suddenly, even though there was no danger present (sometimes while they were traveling at highway speeds). Others said the brakes didn’t engage “as expected” when there was danger.

From the story:

Fourteen complaints involved a crash, with most of those drivers describing the car braking so suddenly it was rear-ended by a trailing vehicle. One driver reported losing control of the car when it unexpectedly hit the brakes at highway speed, causing it to spin out and crash into a guardrail.

No fatalities were reported in the complaints, but three indicated the crashes resulted in injury. Another 18 people reported being hurt by the abruptness of the car activating the brakes without a collision. Some drivers also complained the feature stopped their car unexpectedly over a railroad crossing.

Cynthia Walsh, the owner of a 2018 Nissan Rogue, said she was driving the sport-utility vehicle on the highway in February at 65 miles an hour when the car slammed on the brakes for no apparent reason.

“I was so scared,” Ms. Walsh said. “I was in tears.”

She took the vehicle to the dealership twice for fixes, but she said the problem persists. Now, she said, she is frightened to drive it.

I can’t really blame her. That does sound scary!

While NHTSA does say automatic braking can cut down on the seriousness of crashes and save lives, it also warns the tech isn’t uniformly defined in the industry, partly because it’s so new. Technology in a car sold by Carmaker A could vary wildly from one sold by Carmaker B in what it’s capable of and how it should be used, which is confusing. Some buyers sometimes aren’t even aware their car has such abilities.

Until there is some regulation to how automakers roll out and utilize safety tech for consumers, I predict at least a few more years of confusion. The best advice I can give is to research the hell out of the car you’re about to buy, learn everything you can about it so fewer things take you by surprise.

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