The National Highway Traffic Safety Administration (NHTSA) is Full Self-Driving (FSD) feature in relation to four crashes. The collisions took place in reduced-visibility conditions with either the beta or supervised versions of FSD enabled. In a November 2023 incident in Arizona, a Model Y fatally hit a pedestrian, as notes. An injury was sustained in one of the other three collisions, which occurred between March and May this year and all involved Model 3 .

The NHTSA says conditions such as sun glare, fog and airborne dust lowered visibility in these incidents. The agency’s Office of Defects Investigation (ODI) is looking into FSD’s ability to “detect and respond appropriately to reduced roadway visibility conditions.” It will also try to determine if there have been other crashes in similar circumstances with FSD enabled. The ODI will also probe any changes by Tesla to the system “that may affect the performance of FSD in reduced roadway visibility conditions. In particular, this review will assess the timing, purpose and capabilities of any such updates, as well as Tesla’s assessment of their safety impact.”

In April, the NHTSA into hundreds of crashes in which Tesla’s Autopilot system was engaged. It said 13 of those crashes were fatal. The agency determined that, in many of the crashes, the drivers “were not sufficiently engaged” and that “the warnings provided by Autopilot when Autosteer was engaged did not adequately ensure that drivers maintained their attention on the driving task.”

Tesla CEO Elon Musk just last week claimed that the Model 3 and Model Y SUV will be able to operate without supervision in California and Texas starting next year. At the same event, Musk , a two-seater robocab with no steering wheel or pedals that the company intends to start producing by 2027.

Tesla does not have a media relations department that can be reached for comment.