Police say that the Tesla was driving at slow speeds on a freeway overpass in Glendale, California, but automatically came to a stop when a California Highway Patrol car stopped in front of it.
In radio transmissions the troopers could be heard describing how the car was driving itself with the unconscious driver in it.
“The reporting party is advising that his wife is unconscious in a Tesla. The vehicle is driving itself,” the emergency dispatcher said on the recordings.
“It ended up TC’ing (traffic collision) into the right shoulder wall, and, uh, still continuing.”
The dispatcher then added that the suspect’s husband was following the Tesla in his Volkswagen car.
“Again, apparently the wife is unconscious in the vehicle,” the dispatcher said.
“And I guess there’s vehicles in front of it, that’s what’s causing the vehicle to slow down.”
After officers forced the Tesla to stop they said they woke the driver and conducted a DUI test.
CHP says that Karla Villanueva, 31, was then arrested on suspicion of DUI and booked into the Metropolitan Detention Center Jail.
Tesla is on the verge of a wider roll-out of its Autopilot software and earlier this summer made it available for a monthly subscription.
Last month, the US National Highway Traffic Safety Administration (NHTSA) announced that it has opened an investigation into the Autopilot system and its possible involvement in 11 crashes with emergency vehicles since 2018.
In those crashes, 17 people were injured and one was killed, the NHTSA said.
An investigation could lead to a recall or other enforcement action by the agency.
The head of the National Transportation Safety Board (NTSB) has also called Elon Musk’s company using the term Full Self-Driving as “misleading and irresponsible”.
And Jennifer Homendy has urged the company to delay its roll-out as “It has clearly misled numerous people to misuse and abuse technology.”
Tesla uses the vehicle’s system of cameras and also radar to spot obstacles and decide what action the car should take.