Federal safety regulators have upgraded their investigation into Tesla's Full Self-Driving (Supervised) software, broadening the inquiry to cover around 3.2 million vehicles, according to multiple reports published Thursday.
The National Highway Traffic Safety Administration's escalation focuses on FSD performance in poor weather and reduced visibility conditions, where the system has been linked to crashes. The Wall Street Journal reported that the probe's elevation could lead to a recall campaign or other formal enforcement action.
The development marks a significant regulatory step for Tesla. An engineering analysis phase, which the upgrade implies, typically precedes a recall demand and signals that NHTSA has identified a safety defect warranting closer scrutiny. A recall of 3.2 million vehicles would rank among the largest in Tesla's history and would require the company either to issue a software update or, in a more severe outcome, to disable the feature pending a fix.
Tesla has previously managed NHTSA scrutiny of its driver-assistance systems through over-the-air software patches, avoiding formal recalls in several prior investigations. Whether that pathway remains available will depend on whether regulators accept a software remedy as adequate to address the identified hazard.
The timing adds pressure to a company already navigating weaker delivery numbers and a CEO whose public profile has become a source of commercial and reputational risk. NHTSA has not yet issued a recall order, and Tesla has not publicly commented on the upgraded investigation.
