WASHINGTON (Reuters] – Thursday’s announcement by the National Highway Traffic Safety Administration (NHTSA), that they are upgrading their probe into 830,000 Tesla vehicles (NASDAQ:), with Autopilot, its advanced driver assistance system.

After a string of Tesla-related crashes, NHTSA opened August’s preliminary evaluation in order to evaluate the system’s performance in 765,000 vehicles. NHTSA has upgraded its probe to include an engineering analysis. This is a necessary step to prevent it from requesting a recall.