By Ryan Beene, Bloomberg
US auto safety regulators escalated an investigation of Tesla Inc.’s partially automated driving system marketed as “Full-Self Driving,” citing additional crashes pointing to potential flaws in the technology’s ability to handle driving conditions with reduced visibility.
A review of the incidents raised concern that the system fails to detect and warn drivers appropriately when the visibility of the vehicle’s cameras is degraded, the National Highway Traffic Safety Administration said in a memo posted to its website. The agency this week upgraded its probe, started in 2024, to what it calls an engineering analysis.
Tesla didn’t immediately respond to a request for comment from Bloomberg News.
The move, which could provide the basis for NHTSA to eventually seek a recall, heightens scrutiny of technology that underpins Tesla’s future ambitions around autonomous driving and robotaxi operations. Chief Executive Officer Elon Musk has said the automaker’s ability to develop autonomous-vehicle technology ultimately will determine whether the company is worth lots of money, or “basically zero.”
Tesla’s shares fell 2.5% at 9:31 a.m. Thursday in New York. The stock declined 13% this year through Wednesday’s close.
The new NHTSA memo disclosing the probe identified nine crashes involving the automated system, up from four when it first began investigating in 2024. In crashes the agency reviewed, “the FSD system did not detect common roadway conditions that impaired its visibility and/or provide alerts when camera performance had deteriorated until immediately before the crash occurred.”
NHTSA said Tesla cited company “data and labeling limitations” when seeking to identify additional similar incidents, which the agency said could have led to an under-reporting of crashes during some time periods.
See Also: Tesla Probed by US Agency Over Reporting Crashes Months Late
The probe also raises questions about the effectiveness of an update Tesla developed to detect and address reduced visibility conditions that Musk cited on a quarterly earnings call last year. NHTSA said its defect investigations office has no information about when the system update was deployed and on which vehicles.
A Tesla review of the nine incidents found that had that update been installed, it would have affected three of those crashes, NHTSA said. The agency also said Tesla’s responses revealed additional crashes in which the system “either did not detect a degraded state” or failed to alert the driver with enough time to react.
NHTSA has a number of other ongoing safety investigations involving Tesla vehicles, including probes of the automaker’s door handles and incidents in which Tesla vehicles drove through red lights while using Full Self-Driving.
(Updates with opening shares, NHTSA probe details starting in the fifth paragraph.)
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