MERCEDES-BENZ

Mercedes Steer-by-Wire: the steering wheel that isn't attached to the wheels

"If the steering wheel is still round after 100 years... there's a reason," automotive purists claimed when Tesla launched its innovative joystick-shaped steering wheel in the Model S Plaid (which, incidentally, had to be withdrawn from circulation later). Well, now Mercedes-Benz is going to challenge that axiom...and not just because of its unusual shape.

This is also due to the technology, the invisible elements that connect the steering wheel to the wheels. Until now, there was a physical connection between these two components, through the steering column. But in the future Mercedes EQS (the top-of-the-line model in the brand's electric range), this will change.

This is because the Stuttgart-based company has developed the Steer-by-Wire system, an electronic steering system in which the steering wheel and wheels are not physically connected. They communicate through electrical impulses: when the driver turns the steering wheel, a "brain" sends the command to the wheels, which then execute the maneuver.

We first felt electric steer-by-wire—where there’s no mechanical link between the wheel in your hands and the steering gear controlling the front wheels—on the 2014 Infiniti Q50. It allowed neat features like an infinitely variable steering ratio and an absence of unwanted feedback (from severe bumps, for example). But the Q50 had a safety net: A full steering column still existed, so that if something went wrong, a clutch reconnected a physical shaft, restoring old fashioned steer-by-steel.

Today, there are a handful of vehicles using systems like this, but the first two to eliminate that reconnectable shaft were the (the 2025 Best Tech–winning) Tesla Cybertruck in North America, and the Nio ET9 in China. Mercedes-Benz is poised to be the first German automaker to offer true by-wire steering, launching first in its 2027 Mercedes-Benz EQS-Class sedan. We’ve driven all three and are ready to compare and contrast them.

Fail-Safe...In the Mercedes, whenever an error is detected in either circuit, the car enters a limp-in mode restricting speed to 54 mph, with a maximum driving distance chosen to allow an EQS to safely exit Earth’s longest highway tunnel—the 15.2-mile Laerdal in Norway. And in the infinitesimally small likelihood that both systems were to go down simultaneously, the system will utilize rear-wheel steering and selective braking to achieve the driver’s intended path (we know Nio does this, as well, and Tesla may also). Nio’s behavior upon fault detection is similar—force the car over sooner rather than later, while Tesla flashes lots of warnings but allows the driver to continue using the backup system, with less reduction in functionality and no self-parking end-game.

According to Mercedes-Benz, this electronic steering system offers several advantages for the driver... although there will be an adaptation period, as it will likely change the feeling behind the wheel.

The first advantage is that less effort will be required, which will increase comfort (although with electric power steering this was already not a problem), which will also contribute to the reduction of vibrations transmitted by the wheels - especially on uneven surfaces - which are no longer physically connected to the steering wheel.

Maneuvers (especially for parking) will be easier, but stability at high speed and, above all, agility in curves will also be improved. The suspension and steering on the rear wheels have been calibrated to work in perfect harmony with the electronic steering system (steer-by-wire), which has been perfected over more than one million kilometers of testing.

By not completing the upper edge, the visibility of the instrument panel will be improved. The absence of the steering column also allows the steering wheel to be positioned closer to the dashboard, increasing the space available for the driver. And, overall, the dashboard has a distinctly more modern look.

The shape of the steering wheel has an explanation...The characteristics of the Steer-by-Wire system allowed Mercedes to "play" with a classic element: the shape of the steering wheel. The future EQS will not have a round steering wheel, or at least it will offer an innovative model: more like that of an airplane than that of a traditional car, without the upper part of the rim and with the lower part not only flattened, but also lowered upwards.

You may be wondering what will happen when you need to turn the steering wheel a lot, for example, when parking. But the answer is simple: nothing, because you won't need to.

Another advantage of the electronic steering system is that less movement on the steering wheel results in greater vehicle rotation. In fact, a full rotation requires only 170 degrees of steering wheel movement, meaning you can do it without even taking your hands off the wheel (similar to Formula 1).

Therefore, with this Mercedes electronic steering, it's not necessary for the steering wheel to be round because, in theory – we'll have to test it in practice – we'll never need to cross our arms to make a turn or maneuver.

The electronic steering system (steer-by-wire) will be optional on all versions of the future EQS. If you're not convinced, you can always opt for conventional electromechanical steering.

Autonews