The Office of Defects Investigation (ODI) is opening this Engineering Analysis to evaluate Tesla’s Full Self Driving Beta and Full Self Driving (Supervised) (collectively, FSD) degradation detection system. The focus of this investigation will be to assess the system’s ability, when encountering reduced roadway visibility conditions, to detect degradation and alert the driver with sufficient time to respond. ODI will evaluate the performance of FSD in degraded roadway conditions and the updates or modifications by Tesla to the degradation detection system, including the timing, purpose, and capabilities of the updates, and Tesla’s assessment of their safety impact. Tesla’s FSD is an advanced driver assistance system (ADAS) that relies exclusively on vision-based cameras and the related FSD software to detect and respond to the roadway ahead, projecting a path forward based on traffic control devices, vehicles, pedestrians, and the roadway itself. When Tesla began transitioning away from using both cameras and radars to an exclusively camera-based approach, known as Tesla Vision, in mid-2021, it developed and implemented a degradation detection system that it deployed by a software update to existing and new Tesla vehicles. On June 28, 2024, the day after Tesla submitted the SGO report of the November 28, 2023 fatal crash listed in this document, Tesla began developing an update to the degradation detection system. At this time, ODI does not have information on when the update was deployed and which vehicles have the updated system. ODI discussed individual incidents and its initial findings during the PE phase of its investigation with Tesla. As part of those discussions, Tesla’s post-incident analysis indicated that the update to the degradation detection system, had it been installed on the vehicles at the time, may have affected 3 of the 9 incidents identified by ODI. Tesla also described internal data and labeling limitations that prevented a uniform identificat