NHTSA Investigation PE24025

Lane Keep Assist System

On September 10, 2024, the Office of Defects Investigation (ODI) opened Preliminary Evaluation (PE) 24025 to assess allegations of lane departures with the Lane Keep Assist (LKA) system engaged in Model Year (MY) 2023 through 2024 VinFast VF8 vehicles. The reports further alleged that the system exhibited difficulty detecting lanes on the roadway and, under certain conditions, provided improper steering inputs that resulted in an inconsistent control effort required by the driver, potentially elevating the risk of a crash or injury. To date, ODI has received a total of 17 related Vehicle Owner Questionnaires (VOQ) of the LKA system in the subject vehicles. As a part of the investigation, NHTSA’s Vehicle Research and Test Center (VRTC) replicated the VOQ- reported conditions in a MY 2024 VinFast VF8. VRTC documented that two conditions within  the MY 2024 VinFast VF8 LKA system may induce the vehicle to deviate laterally outside of the intended travel lane when navigating sweeping roadway curves. First, during sweeping turns, the steering wheel force required may abruptly change mid-turn, altering the steering wheel force equilibrium between driver input and roadway force, potentially causing the driver to unintentionally steer excessively leading vehicle to cross over its lane boundaries. Second, the LKA system may apply steering inputs to maintain the curve that move the vehicle toward the inside lane line and, in some cases, across the lane boundary, increasing the risk of a collision. On August 27, 2025, VinFast filed NHTSA Recall No. 25V-559 to address the safety-related defect in the LKA system. This recall consists of a software update that is intended to refine the system’s steering control and improve the overall driving smoothness. Specifically, the software update will: (i) reduce steering wheel vibration during the activation of the vehicle’s advance driver-assistance system (ADAS); (ii) make it easier for the driver to override the ADAS; and (iii) smooth the transition between an active and inactive LKA system, so that driver inputs deactivating the system may not cause unintended vehicle maneuvers. Because this recall action is taken by VinFast, ODI is closing PE24025. NHTSA reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov. The opening resume identified VOQ #11585817 as a fatal crash involving a vehicle roadway departure at high speed. ODI’s analysis found the crash conditions are not consistent with those observed during VRTC testing for this investigation. The subject vehicle’s Event Data Recorder (EDR) sustained fire damage during the collision, rendering the recorded data inaccessible at this time. ODI has no evidence linking this crash to the LKA behavior identified in PE24025 and will continue to monitor for any additional information that might warrant further assessment of this incident.

An investigation is a separate record from a recall and from a manufacturer communication. A manufacturer campaign to repair a safety defect or a failure to meet a federal safety standard.