Federal safety regulators are intensifying their scrutiny of Tesla’s Full Self-Driving (FSD) system, as the National Highway Traffic Safety Administration (NHTSA) announced on March 18, 2026, that it is escalating its current investigation to an Engineering Analysis.
This development impacts approximately 3.2 million vehicles, encompassing nearly every Tesla model manufactured over the past decade, including the Model S, X, 3, Y, and Cybertruck.
The Office of Defects Investigation (ODI) is specifically honing in on how FSD performs in “reduced roadway visibility” scenarios, such as intense sun glare, fog, or airborne dust that can impede camera functionality. According to investigation documents, there are concerns that the system may not effectively recognize when its visual capabilities are compromised and may not provide adequate warnings to the driver in time to resume control.
The catalyst for this heightened scrutiny stems from a string of nine incidents involving Tesla vehicles equipped with FSD that were involved in accidents during low-visibility conditions. These incidents resulted in two injuries and one tragic fatality, with reports indicating that the FSD system either lost track of or failed to detect the vehicle directly in front of it in several cases.
Regulators are particularly focusing on Tesla’s decision to shift to a “Vision” approach reliant solely on cameras, eschewing radar. While Tesla made this transition in 2021, the NHTSA is questioning the efficacy of software updates intended to detect camera degradation. Tesla’s own analysis suggested that a recent software update may have played a role in three of the nine crashes identified by investigators, although uncertainty surrounds the timeline of this update’s deployment across the fleet.
Moreover, the NHTSA highlighted Tesla’s internal data constraints that may have contributed to the underreporting of similar incidents. By elevating the investigation to an Engineering Analysis, the government can demand more comprehensive information from Tesla regarding the timing and effectiveness of their safety enhancements.
As Tesla navigates this intensified regulatory scrutiny, the company is under mounting pressure to address concerns surrounding the performance of its FSD system in challenging visibility conditions. Stay tuned for further updates as this investigation continues to unfold.