Federal highway safety officials, deepening their investigation of Tesla Motors and its Autopilot technology, have asked questions about the company’s crash-prevention systems and any incidents in which they failed to work properly, including the May 7 crash that sparked the inquiry.

The request, which the National Highway Traffic Safety Administration (NHTSA) announced on Tuesday, is part of an increase in federal scrutiny of Tesla. A separate agency, the National Transportation Safety Board, is also looking into the crash that killed Joshua Brown, an entrepreneur from Ohio.

Brown’s 2015 Tesla Model S collided with a semitrailer truck in Florida while the car’s Autopilot was engaged.

The questions indicate NHTSA is investigating whether there are defects in the various crash-prevention systems related to the Autopilot system, including automatic emergency braking and Autosteer, which uses radar and camera input to guide the vehicles on highways or in slow-moving traffic.

The company warns drivers to keep their hands on the steering wheel and remain alert while using Autopilot. Since the May 7 crash, the company has emphasized that Autopilot is not a fully automated driving system.

New York Times