A member of the media test drives a Tesla Motors Model S car equipped with Autopilot in Palo Alto, California.

Tesla Motors' shares barely budged on Friday following news that U.S. regulators opened an investigation into the automaker due to a fatal crash.

The National Highway Traffic Safety Administration is looking into the "Autopilot" feature in Tesla's Model S cars, and this examination is the first step that may lead to recalling vehicles if declared unsafe.