A Feature Synonymous With Tesla Is Now Under Investigation by Federal Authorities

Tesla is known for its Full Self-Driving (Supervised) feature, which packs automatic parking, lane changes and steering on city roads into an $8,000 upgrade for buyers. Though FSD is popular , new records filed on Friday morning show that a federal agency is concerned about the system's safety.

The National Highway Traffic Safety Administration (NHTSA) opened a preliminary investigation into all 2.4 million Tesla vehicles with FSD, including the Model 3 and Model Y, two of the most popular electric vehicles sold in the U.S. last year. The investigation follows four crashes involving Tesla cars; one resulted in a fatality, and one caused an injury.

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The incidents were caused by low visibility conditions, like sun glare or fog, which interfered with FSD, the NHTSA wrote in the report . The preliminary review will look into how well FSD responds to low visibility conditions, if other FSD crashes happened under similar circumstances, and if Tesla makes any updates to the FSD system to improve safety.

^{Tesla Model 3. (Photo by Stanislav Kogiku/SOPA Images/LightRocket via Getty Images)}

NHTSA's investigation arrived one week after Tesla held its robotaxi event . Robotaxis are meant to be fully autonomous, which Tesla itself acknowledges is difficult to achieve.

"Full autonomy will be dependent on achieving reliability far in excess of human drivers as demonstrated by billions of miles of experience, as well as regulatory approval, which may take longer in some jurisdictions," Tesla wrote on its website .

Tesla remains the market leader in electric vehicles, selling more than 1.8 million cars in 2023 alone. Its most recent earnings report, released earlier this month, shows that it delivered nearly half a million cars in Q3 alone, with delivery numbers up 6% from last year.

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