Level 3 Autonomy

Experts divide self-driving cars into six levels, from 0 to 5. Level 0 means: the human does everything themselves. Level 5 means: the car drives everywhere and always on its own, a steering wheel would be superfluous. Level 3 autonomy lies in between and marks an important break. Up to Level 2, the human must constantly keep an eye on traffic, even when the car is steering and braking. From Level 3 onwards, they are allowed to look away for the first time, as long as certain conditions are met. The car then takes over monitoring the surroundings completely.

The point at which responsibility shifts

Level 3 is legally the most exciting stage. At Level 2, the driver is always liable, since they are supposed to pay attention. At Level 3, the manufacturer bears responsibility during automated driving. If an accident happens during this time, the driver can no longer be held solely responsible. This is precisely why carmakers and legislators struggle so much with this level.

For the auto industry, Level 3 is a high-risk selling point. Whoever gets the technology approved first gains prestige and a head start. Whoever offers it too early risks recalls, lawsuits, and headlines. Germany created a law for such systems in 2021, one of the first countries to do so. Mercedes-Benz was subsequently allowed to sell the first officially approved Level 3 traffic jam assistant in 2022.

There is also a critical counter-position. Some safety researchers consider Level 3 to be the most dangerous of all stages. The reason: a person who has been watching videos for ten minutes reacts poorly to a sudden prompt. Companies like Waymo therefore deliberately skip Level 3 and work directly on higher levels.

Operating range and takeover request

Every Level 3 system has a defined operating range. Experts call it the Operational Design Domain, meaning the area for which the system was designed. The Mercedes assistant, for example, may only operate on approved highways, only in dense traffic, only up to 95 km/h, and not in heavy rain. Within these limits, the car drives itself; outside them, it doesn’t even switch on.

Technically, several types of sensors are involved simultaneously. Cameras detect lane markings and signs. Radar measures distances and speeds of other vehicles. A lidar scans the surroundings with laser beams and creates a spatial image. Software evaluates all these data streams together, so that the failure of a single source doesn’t leave the system blind.

The critical moment is called the takeover request. When the car reaches the limit of its operating range, it warns with sound, display, and sometimes a seatbelt tug. The driver then typically has about ten seconds. If they don’t respond, the system must bring the vehicle to a controlled stop itself and switch on the hazard lights. Interior cameras therefore check whether the driver is still awake and responsive.

What’s actually on the road today

Level 3 features are still rare and expensive on the market. Mercedes offers the traffic jam assistant in the S-Class and the EQS, BMW has a similar system in the 7 Series. Both only work in traffic jams or slow-moving traffic. Honda sold a small series with comparable technology in Japan. For most drivers, Level 3 thus remains a thing of the future.

A common misconception concerns Tesla's software. Names like Autopilot or Full Self-Driving sound like more, but are officially Level 2. There, the driver must pay attention to traffic at all times and is liable themselves. Anyone who knows this distinction reads advertising promises much more soberly.

In business news, the term usually comes up in connection with approvals and setbacks. Reports about new approvals in China, Japan, or individual US states move the stock prices of carmakers and chip manufacturers. That’s because the computing power for such systems comes from specialized processors, which companies like Nvidia and Qualcomm profit from. Level 3 is thus not just a traffic issue, but also a billion-dollar market.