NHTSA Proposes Cyan Lights for All US Driverless Vehicles

The National Highway Traffic Safety Administration has officially proposed a new visual standard for autonomous vehicles. The agency wants driverless cars to display a distinct blue-green light to signal to the world that no human is at the wheel. This move ends a long period of debate among industry stakeholders about the best way to communicate the status of a robotaxi. Previous discussions involved various ideas, including flashing text, audio alerts, and custom lighting configurations. The feds have now settled on a single, unified approach to streamline the process for manufacturers and drivers alike.

The proposal involves specific changes to Federal Motor Vehicle Safety Standard No. 108. Regulators are rewriting these rules to accommodate the unique needs of autonomous technology. The primary goal is to create a consistent method for robotaxis to communicate with law enforcement and other road users. The agency believes a cyan-colored marker lamp is the optimal solution for this purpose. This color choice is intended to fill a visual gap in the current traffic lighting system without causing confusion among other motorists.

The decision to select cyan is rooted in existing industry practices. Currently, the automotive sector relies on red, amber, white, and flashing blue or red lights for standard functions like brakes, turn signals, headlights, and emergency alerts. By introducing a blue-green hue, NHTSA aims to distinguish autonomous operation from these traditional signals. There is precedent for this approach, as Mercedes-Benz previously received state-level approval for turquoise lights on its Level 3 Drive Pilot vehicles. Although the automaker has since moved toward a different system, the federal agency sees value in establishing a national standard.

Under the new proposal, cyan marker lights would be optional for manufacturers. However, if an automaker chooses to implement them, they must adhere to strict federal standards regarding color, brightness, and location. This ensures a consistent and legal setup across the board, preventing a confusing mix of different colors and signals. Major players in the space, including Waymo, Nuro, Zoox, GM, and Mercedes, could adopt this uniform standard. This consistency is crucial for public safety and regulatory clarity as these vehicles become more common on American roads.

The agency is also proposing to remove several lighting requirements that do not apply to vehicles without human drivers. Current rules mandate the presence of physical hazard switches, manual beam shifters, and turn levers inside the cabin. NHTSA suggests eliminating these requirements to reduce administrative burdens. The update also includes revisions to the 12.8-volt testing standard, allowing automakers to build around modern LED architectures more easily. Additionally, the agency is considering removing rules that dictate the relative positioning of high-beam and low-beam lights.

This update is part of a broader administrative push by the Department of Transportation to streamline the deployment of autonomous vehicles. The government aims to make it easier for companies to build cars without traditional controls like steering wheels and pedals. However, regulators are still enforcing current rules strictly. Last month, NHTSA opened an audit query into the Tesla Cybercab to examine the technical data used for its certification. This investigation focuses on the absence of certain design features, such as sideview mirrors, pedals, and a steering wheel, which are currently required under existing federal safety standards.