The U.S. National Highway Traffic Safety Administration (NHTSA) announced it has closed a preliminary evaluation opened in 2022 into reports of unexpected deceleration affecting roughly 695,000 Tesla vehicles. The probe focused on Model 3 and Model Y vehicles and was ended after the regulator concluded that the issue posed a low demonstrated hazard and that occurrences have declined substantially.
NHTSA's summary of the case notes that Tesla issued software updates in early 2022 aimed at addressing reports of unexpected deceleration. When the investigation began there were about 300 incident reports; the regulator recorded a reduction to 45 reports in 2024, 19 in 2025, and only three reports since the start of 2026.
In closing the inquiry, NHTSA said the reported conditions did not cause the affected vehicles to change their lateral positioning within lanes. The agency also stated the events did not produce a meaningful reduction in distance between the subject vehicles and those following them that would lead to a collision.
The action follows a separate move by the agency last week, when it closed an expanded probe into an estimated 376,241 Model 3 and Model Y vehicles that had been under review for potential loss of steering control.
Context and procedural details
NHTSA characterized the decision to close the preliminary evaluation as based on both the drop in reported incidents after software updates and an assessment of the associated risk to drivers. The agency's observations regarding lateral positioning and following-distance impact were cited as part of its rationale.
While the agency noted only three reports since the start of 2026, the record of earlier reports and the existence of a related, recently closed probe into steering control remain part of the public regulatory record.
Takeaway
- The preliminary evaluation into unexpected deceleration affecting approximately 695,000 Tesla Model 3 and Model Y vehicles has been closed by NHTSA.
- Tesla implemented software updates in early 2022 intended to address the deceleration reports, and incident counts declined from about 300 at the outset to 45 in 2024, 19 in 2025, and three since the start of 2026.
- NHTSA stated that the reported conditions did not alter lateral lane positioning or create significant loss of distance between subject and following vehicles that led to collisions. The agency also recently closed a separate probe covering an estimated 376,241 Model 3 and Model Y vehicles over loss of steering control.