WASHINGTON (BLOOMBERG) - The US has opened a formal investigation of Tesla's Autopilot system, citing collisions with parked emergency vehicles, according to documents posted on Monday (Aug 16) on the National Highway Traffic Safety Administration's website.
The investigation covers an estimated 765,000 Tesla Model Y, Model X, Model S, Model 3 vehicles from the 2014-2021 model years. NHTSA said it launched the probe after 11 crashes or fires that resulted in 17 injuries and one fatality.
"Most incidents took place after dark and the crash scenes encountered included scene control measures such as first responder vehicle lights, flares, an illuminated arrow board, and road cones," the agency said in the document.
"The involved subject vehicles were all confirmed to have been engaged in either Autopilot or Traffic Aware Cruise Control during the approach to the crashes."
Tesla shares fell as much as 2.4 per cent to US$700.16 (S$950) before the start of regular trading. Representatives for the electric-car maker didn't immediately respond to a request for comment.
Autopilot is Tesla's driver assistance system that maintains vehicle speed and lane centring when engaged, but the driver still is responsible for identifying other vehicles and obstacles in the roadway or responding to manoeuvres by neighbouring vehicles.
Critics have suggested it is improperly marketed as a system that is capable of fully automatic driving.
NHTSA investigated Tesla's Autopilot in the wake of a 2016 fatal crash and cleared the system early the following year.
The regulator has opened at least 30 special crash investigations involving Tesla cars that it suspected were linked to Autopilot, with the pace of probes picking up under the Biden administration.
The first of the 11 crashes that prompted the last probe occurred on Jan 22, 2018, in Culver City, California, according to NHTSA. The most recent accident occurred on July 10, 2021, in San Diego.
Other reported accidents occurred in Florida, Michigan, Texas, Arizona, Massachusetts, Indiana and Connecticut.