On an earnings call with investors on Wednesday, Tesla CEO Elon Musk made an extraordinary statement: all of Tesla’s vehicles today are capable of what he has called “full self-driving” on highways and most other controlled-access roads.

“Full self-driving capability is there,” Musk said matter-of-factly. He was referring to Tesla’s recently rolled out “Navigate on Autopilot” feature, which guides the car from “on-ramp to off-ramp” by suggesting and making lane changes, navigating highway interchanges, and proactively taking exits.

Navigate on Autopilot is not “full self-driving,” not even on the highway

The problem is that Navigate on Autopilot is not “full self-driving,” not even on the highway. No car on the road today can completely drive itself — that includes Teslas. Last October, Tesla suddenly yanked the “full self-driving” option from its website, claiming it was “causing too much confusion” for customers to justify keeping it front and center, Musk said at the time. So for Musk to claim that all Tesla vehicles with Navigate on Autopilot are capable of “full self-driving” is confusing and, some would argue, dangerous.

To poke holes in Musk’s comments, you need look no further than the Society of Automotive Engineers (SAE) taxonomy for autonomous vehicles, commonly referred to as the SAE levels, which have become the global standard for defining self-driving. Most experts would categorize Navigate on Autopilot as Level 2 autonomy, meaning the vehicle can handle basic tasks, like acceleration, braking, and lane changes, but the human driver needs to maintain full attention of the road and be prepared to take control of the vehicle in a moment’s notice.

.@elonmusk: "We already have full-self driving capability on highways"



Bullshit. Tesla drivers aren't supposed to stop watching the road, the are responsible for OEDR and fallback. This is level 2. And a dangerous lie. pic.twitter.com/4GFkixfDMZ — E P D (@EricPaulDennis) January 30, 2019

Tesla’s vehicles say so themselves. When activating Navigate on Autopilot, a warning screen pops up on the center display that reads, “Navigate on Autopilot does not make your Model 3 autonomous. Like other Autopilot features, the driver is still responsible for the car at all times.” Drivers who take their hands off the steering wheel risk disengaging the feature.

Not even highly automated vehicles like those operated by Alphabet’s Waymo, Ford’s Argo AI, or GM’s Cruise Automation would really qualify as “full self-driving” because they are only able to operate within a specific geographic location and under specific conditions, like good weather. Those companies typically keep safety drivers behind the wheel, with the understanding that their vehicles would be considered Level 4 capable under the SAE’s taxonomy.

The SAE levels aren’t perfect

The SAE levels aren’t perfect; they tend to gloss over all of the different forms of automation that are under development. Most automakers avoid using the SAE levels when defining their various systems, but they’re all we have at the moment, and government agencies like the US National Highway Traffic Safety Administration use them frequently when discussing vehicle autonomy.

So Musk’s claim that Tesla vehicles today are capable of “full self-driving” is misleading. As we messily transition between the older way of driving and the newer way of being driven, Musk is adding to the confusion. Consumers hear Musk say that Tesla vehicles are “full self-driving,” and they take that to mean they don’t have to pay attention when Autopilot is engaged. And that’s when we get idiot stunts like when a driver in the UK jumped into the passenger seat to film his car driving down the highway.

Even Tesla’s public statements about Autopilot contradict Musk’s comments. When there’s been a crash involving Autopilot (and there have been a few), Tesla will inevitably release a statement hammering this point: drivers need to pay attention to the road, and Autopilot does not prevent all accidents.

Drivers need to pay attention to the road

Experts are beginning to realize that the way we talk about autonomy is a real big deal. Last week, AAA released a survey of major car brands that found that automakers have gone overboard in their naming conventions. There are 40 different brand names used to describe automatic emergency braking, 20 different names for adaptive cruise control, and 19 terms for lane-keeping assistance. Forty percent of Americans think cars with Autopilot can already drive themselves.

During the earnings call, Musk explained the difficulty in getting Autopilot to “99.999 percent” rate of success, citing traffic signals as particularly problematic. He added that the company would be ready to roll out “full self-driving” by the end of the year, depending on local regulatory approval. And later, he referenced Tesla’s developer mode of Autopilot being capable of “full self-driving,” so it’s unclear whether Musk was talking about customer vehicles or not. A Tesla spokesperson declined to comment.

“Full self-driving” has been a long time coming. Four years ago, Musk claimed that Tesla’s vehicles would be capable of completely driving themselves without any human interaction by 2017. Two years ago, Musk announced every car made going forward would have the hardware necessary to facilitate this goal. Tesla has spent the years since advertising this impending breakthrough on its website as an easy add-on to the purchase of a new car, something that only required a few thousand dollars and a little bit of patience.

This isn’t the first time Musk has sparked controversy about Autopilot. Last April, Musk took his hands off the wheel after activating Autopilot in a Model 3 during an interview with CBS This Morning. He did it again during a 60 Minutes interview in December. It’s like he can hardly help himself.