Federal government's top auto -Safety regulator seeks to find out why Tesla did not issue a recall last month when it updated the software on its cars to improve their ability to spot stopped emergency vehicles such as police cars and fire trucks.
The regulator, the National Highway Traffic Safety Administration, also ordered Tesla to provide data on its Full Self-Driving software, which it allowed a small group of owners to test on public roads.
NHTSA opened a formal investigation during the summer of 12 collisions in which Tesla cars operating in Autopilot mode (adriver assistance system which can steer, brake and accelerate a car by itself) failed to detect stopped emergency vehicles with flashing lights in low light conditions.
In a letter to Tesla on Tuesday, the agency reminded the company that federal law requires automakers to issue recalls if they discover faults posing a security risk.
NHTSA has asked the company to provide detailed information about a software update sent in late September that has modified the autopilot and improved its ability to detect hazard lights.
The letter told Tesla to indicate whether it intends to continue a reminder related to the update, and if not, any legal or technical reason why it refuses to do so.
" Any manufacturer issuing an an overhead update that mitigates a defect that poses an unreasonable risk to motor vehicle safety is required to timely file an accompanying recall notice, "said the 'agency in the letter.
The letter was sent by Gregory Magno, head of the
NHTSA also ordered Tesla to provide the number of owners who received software from Complete self-driving and copies of all agreements the company has with owners. Tesla CEO Elon Musk described complete self-driving as a technology that would allow the title cars to drive sostand-alone under most circumstances. But software is not able to drive a car without the active engagement of a human driver.