Federal safety regulators have intensified their investigation into Tesla’s driver-assistance technology, raising new concerns about how the system performs in everyday driving conditions.
According to Reuters, the National Highway Traffic Safety Administration (NHTSA) has upgraded its probe into Tesla vehicles equipped with Full Self-Driving software to an “engineering analysis,” a critical step that often precedes a decision on whether a recall is warranted. For a link to the NHTSA documents click here.
The expanded investigation now covers approximately 3.2 million Tesla vehicles on U.S. roads, making it one of the largest safety reviews ever involving advanced driver-assistance systems. The probe began in October 2024 as a preliminary evaluation involving roughly 2.4 million vehicles but has since grown in scope as regulators reviewed additional data.
At the heart of the investigation is how Tesla’s camera-based system performs in low-visibility situations. Tesla moved away from radar sensors in 2021, relying instead on a camera-only system known as Tesla Vision. Regulators are now examining whether that approach can reliably detect hazards when visibility is affected by sun glare, fog, dust, or other environmental factors.
Investigators are also looking into whether the system properly alerts drivers when its cameras are impaired. According to NHTSA, available incident data raises concerns that warnings may not always occur in a timely manner—or in some cases, may not occur at all—before a crash happens.
Federal officials have identified at least nine crashes that may be tied to the issue, including one fatality and two incidents involving injuries. An additional six crashes are also under review. In several of these cases, the system reportedly failed to detect or maintain tracking of vehicles ahead, raising questions about how the technology handles common roadway scenarios.
Despite its name, Tesla’s Full Self-Driving system is not fully autonomous. It is classified as an advanced driver-assistance system that requires drivers to remain attentive and ready to take control at any time. Tesla has promoted the technology as a cornerstone of its long-term strategy, including future plans for autonomous ride-hailing services.
The latest action adds to ongoing regulatory scrutiny of Tesla’s driver-assistance features, including its Autopilot system. In a separate investigation launched in October 2025, regulators reviewed nearly 2.9 million Tesla vehicles following reports of crashes and potential traffic safety violations.
As part of the current probe, regulators are evaluating a “degradation detection” feature Tesla introduced after transitioning to its camera-only system. That feature is designed to recognize when visibility is compromised and notify the driver. However, according to Reuters, early findings suggest the system may not consistently perform as intended under real-world conditions.
Tesla has indicated that software updates could improve system performance, and company data suggests that some of the crashes under review may have been avoided if newer updates had been installed. Regulators are now examining how widely those updates have been deployed and whether they significantly improve safety outcomes.
Tesla did not immediately respond to a request for comment from Reuters.
The outcome of the investigation could have broad implications, not only for Tesla but for the entire auto industry as automakers continue advancing driver-assistance and autonomous technologies. An engineering analysis is typically the final stage before regulators decide on enforcement action, including the possibility of a recall.
For now, the investigation serves as a reminder that while technology in today’s vehicles continues to evolve rapidly, safety expectations remain firmly grounded in real-world performance.
Editorial credit: Artistic Operations/Shutterstock.com. Houston, TX USA December 24, 2025.
