Tesla's autopilot system

Credit: Bloomberg News

Tesla is under investigation amid fears that flashing lights from emergency vehicles are confusing its electric cars’ Autopilot system and triggering crashes.

The US National Highway Traffic Safety Administration (NHTSA) said it would probe almost a dozen crashes involving Autopilot, the software that regulates a car’s speed and lane positioning.

Regulators have identified 11 crashes in which Tesla cars using Autopilot “have encountered first responder scenes and subsequently struck one or more vehicles involved with those scenes”.

The regulator said most of the collisions happened after dark and involved lights on emergency vehicles such as ambulances and police cars, traffic cones or illuminated arrow boards. There have been 11 such crashes since the start of 2018, resulting in 17 injuries and one death.

In one case in California last month, a Tesla car sped through a road closure into an empty police car. In another crash in Michigan, a Tesla hit a police car with its emergency lights on after an officer had stopped to investigate a collision.

Tesla’s Model 3 was the UK’s best selling car in three separate months last year, and the company installs its Autopilot software on all new vehicles.

According to Tesla their Autopilot cars are much safer than the average car

While it is described as a “driver assistance” system, requiring motorists to maintain ultimate control of a vehicle, the Autopilot system has been criticised for allowing reckless driving.

Last year, a US safety report into a fatal Autopilot accident said that it could lead drivers to be complacent.

Tesla has added safety features, such as sensors that detect if a driver is keeping their hands on the steering wheel. Elon Musk, its chief executive, has declared that the system is safer than human drivers and said that fewer accidents occur per mile when Autopilot is engaged.

The company’s shares fell by as much as 5pc on Monday after news of the investigation emerged, reducing its value by more than $30bn (£22bn). The NHTSA said the Autopilot software features in 765,000 Tesla cars sold in the US since 2014.

Mr Musk is due to present a Tesla “AI day” later this week,  in which the company will tout advances in self-driving technology. Tesla has already started allowing enthusiasts to test its “full self-driving” system, which takes control of all driving functions.

The Government plans to make hands-free driving on British motorways legal by the end of the year, although it will at first limit this to speeds no higher than 37 mph.

Tesla did not respond to a request for comment.