maybe ban it instead — NHTSA has tested the updated system and still has questions. Enlarge / A 2014 Tesla Model S driving on Autopilot rear-ended a Culver City fire truck that was parked in the high-occupancy vehicle lane on Interstate 405. Tesla's lousy week continues. On Tuesday, the electric car maker posted its quarterly results showing precipitous falls in sales and profitability. Today, we've learned that the National Highway Traffic Safety Administration is concerned that Tesla's mass...