The National Highway Traffic Safety Administration has expanded its probe into Tesla's Full Self-Driving system, focusing on failures in its degradation detection software. Nine crashes - including one fatality - occurred when the system failed to recognize impaired visibility due to glare or obstructions.
The investigation covers 3.2 million Tesla vehicles in the U.S., nearly the company’s entire domestic fleet. Regulators found the system did not issue timely warnings, often failing until moments before impact.
Tesla’s post-incident analysis suggested a software update may have contributed to three of the nine incidents. The NHTSA noted additional crashes in similar conditions where drivers received insufficient response time.
The probe could trigger a recall or enforcement action if a safety defect is confirmed.
Tesla has not responded to requests for comment.