Tesla shares fell 1.29% in premarket trading.The National Highway Traffic Safety Administration (NHTSA) said Thursday it is opening a formal investigation into 416,000 Tesla vehicles over reports of unexpected brake activation tied to its driver assistance system Autopilot.
The preliminary evaluation covers 2021-2022 Tesla Model 3 and Model Y vehicles in the United States after the agency received 354 complaints about the issue over the past nine months. NHTSA said the vehicles under review have a advanced driver assistance system that Tesla calls Autopilot that allows them to brake and steer automatically within its lanes.
NHTSA said: "Complainants report that the rapid deceleration can occur without warning, at random, and often repeatedly in a single drive cycle."
Earlier this month, NHTSA confirmed it was reviewing consumer complaints that Tesla vehicles were activating the brakes unnecessarily. A preliminary evaluation is the first phase before NHTSA could issue a formal recall demand.