A U.S. regulator have opened up the biggest review of Tesla Inc.’s Autopilot system since the driving-assistance feature was introduced, centered around almost a dozen collisions at crash scenes involving first-responder vehicles, stepping up its scrutiny of a system the carmaker has charged thousands of dollars for over the last half decade.

The probe by the U.S. National Highway Traffic Safety Administration (NHTSA) covers an estimated 765,000 Tesla Model Y, X, S and 3 vehicles from the 2014 model year onward. The regulator — which has the power to deem cars defective and order recalls — said it launched the investigation after 11 crashes 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.”

Autopilot is Tesla’s driver-assistance system that maintains vehicles’ speed and keeps them centered in lanes when engaged, though the driver is supposed to supervise at all times.

The company has been criticized for years for naming the system in a potentially misleading way. Since late 2016, it has marketed higher-level functionality called Full Self-Driving (FSD) Capability . It now sells that package of features — often referred to as FSD — for US$10,000 or a US$199 a month.

A NHTSA spokesperson said the agency’s preliminary investigation will focus on Tesla’s autopilot system and “the technologies and methods used to monitor, assist, and enforce the driver’s engagement with driving while Autopilot is in use.” The agency is looking at accidents in which one of two Tesla systems — Autopilot or Traffic Aware Cruise Control — was engaged.

The 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.

(SD-Agencies)