Tesla’s reputation for making technologically advanced cars took a hit on Tuesday when the company recalled more than two million vehicles under pressure from regulators who said it did not do enough to ensure that drivers remain attentive when using a system that can steer and brake cars automatically.
The recall by Tesla, the world’s dominant maker of electric vehicles, was its fourth in less than two years and the most significant to date. It covers nearly all cars the company has manufactured in the United States, including its most popular, the Model Y sport-utility vehicle.
The recall follows an investigation into Autopilot that the National Highway Traffic Safety Administration began in August 2021 after a series of accidents involving the technology. Autopilot is designed to steer, brake and accelerate vehicles on its own when on highways. With its latest recall, Tesla made it clear that it did not agree with agency’s assessment of the system. The regulator said its investigation would continue.
“It’s critical that N.H.T.S.A. has kept this investigation open to see if the changes actually reduce the risks,” said Matthew Wansley, professor at the Cardozo School of Law in New York who specializes in emerging automotive technologies.
The investigation is the most prominent example of a wider push and pull among government regulators and a wide range of companies developing technologies that allow vehicles to drive on their own in certain situations.
In October, California regulators ordered Cruise, a General Motors subsidiary, to stop its driverless taxi service in San Francisco after a series of traffic mishaps, including one in which a Cruise car dragged a pedestrian 20 feet after a crash. The company has since suspended its operations across the country.
Tesla’s latest Autopilot update will add new, more prominent visual alerts and checks for the Autosteer function that is part of Autopilot. There may be “increased risk of a crash,” the safety administration said, when Autosteer is engaged and drivers do not “maintain responsibility for vehicle operation.”
The agency said that in August 2021 it began investigating 11 incidents involving Tesla vehicles that were operating with Autosteer engaged. A series of meetings between the agency and Tesla followed, and the company decided this month to voluntarily administer a recall.
Tesla’s latest recall does not end the agency’s investigation, which is well into its third year, according to a letter to Tesla from the safety administration.
“Automated technology holds great promise for improving safety but only when it is deployed responsibly,” the agency said in a statement sent to The New York Times. “Today’s action is an example of improving automated systems by prioritizing safety. “
Tesla’s chief executive, Elon Musk, did not respond to a request for comment.
Over the course of its investigation, the safety agency said, it has reviewed 956 crashes in which Autopilot was engaged before focusing on 322 crashes, including frontal collisions and situations where Autopilot may have been accidentally engaged.
Tesla began issuing wireless software updates to certain vehicles this week, safety officials said. The remaining vehicles will receive updates later, and all updates will be free for the cars’ owners.
The update will add controls and alerts to Autosteer. Depending on the hardware on a car, some updated vehicles will feature more prominent visual alerts as well as additional checks upon using Autosteer. The feature will also be suspended if drivers repeatedly fail to use it responsibly.
Letters to Tesla owners notifying them of the update are expected to be mailed in February.
Tesla’s recall this week is the latest in a string of events that have brought scrutiny to the automaker and its software. In October, a California jury found that the company’s driver-assistance software was not at fault in a crash that killed a Tesla owner and seriously injured two passengers.
The company has also faced a series of recalls. In May, China ordered Tesla to recall 1.1 million vehicles, citing an issue with the acceleration and braking systems of certain models manufactured in China and abroad.
A few months earlier, Tesla recalled more than 362,000 cars equipped with its Full Self Driving driver-assistance system, a more advanced technology than Autopilot, after government regulators found it increased the risk of accidents. With Full Self-Driving, Tesla is seeking to extend Autopilot beyond highways and onto city streets.
The more advanced system allows vehicles to travel above legal speed limits and through intersections in “an unlawful and unpredictable manner,” safety officials said.
And in early 2022, Tesla recalled 54,000 cars equipped with its Full Self Driving software to disable a feature that in certain conditions let the vehicles roll slowly through intersections without making required stops.
Tesla sells Full Self Driving separately from Autopilot. But the two services are underpinned by the same set of technologies. In the past, drivers who have not purchased the more advanced system have still been able to use Autopilot on roads that are not highways.
The company’s latest recall explains that drivers will be alerted when they are using Autopilot outside of highways where the technology is intended to operate. But it is unclear whether they will still be permitted to use the technology in these situations.
“N.H.T.S.A. has forced Tesla to focus on the right issues,” Mr. Wansley said. “But everything depends on the details.”