WASHINGTON — U.S. auto safety regulators have opened an investigation to assess potential safety issues in certain Tesla Inc. vehicles after reports alleging "phantom braking."
NHTSA's Office of Defects Investigation said it has received 354 complaints in the past nine months for unexpected brake activation.
The safety probe covers an estimated 416,000 Tesla Model 3 and Model Y vehicles from the 2021-22 model years that are equipped with the electric vehicle maker's advanced driver-assistance system, Autopilot.
The complaints allege that while using Autopilot's features, such as adaptive cruise control, "the vehicle unexpectedly applies its brakes while driving at highway speeds," according to the agency's report.
"Complainants report that the rapid deceleration can occur without warning, at random and often repeatedly in a single drive cycle," the report reads.
A Washington Post report this month said NHTSA had received more than 100 reports of phantom braking in three months.
Owners say they have raised concerns with Tesla, which has dismissed the complaints, saying the braking is normal.
The owner of a 2021 Model Y told NHTSA in October that while they were driving on a highway, "the car braked hard and decelerated from 80 mph to 69 mph in less than a second. The braking was so violent, my head snapped forward and I almost lost control of the car."
Tesla, which disbanded its media relations department, did not respond to a request for comment.
Jonathan Adkins, executive director of the Governors Highway Safety Association, the group that represents state highway safety agencies, said on Twitter, "Another day, another issue with Tesla. Good to see NHTSA being more active in [reining] this company in."
The latest investigation into Tesla vehicles comes as the EV maker faces greater regulatory scrutiny. It also follows a series of recalls by the automaker and two other safety probes by the agency.