Driverless cars may glow cyan under new federal lighting draft

Drivers sharing the road with robotaxis could soon see a distinct blue-green glow on vehicles operating without a human at the wheel. The National Highway Traffic Safety Administration released proposed amendments to Federal Motor Vehicle Safety Standard No. 108 this week. The changes aim to create a unified visual signal for automated driving systems.

NHTSA proposes cyan marker lamps to solve a long-standing debate in the autonomous vehicle industry. The agency states the lights would clearly signal to law enforcement and other road users that an automated system is in control. Officials selected cyan because red, amber, white, and flashing blue or red lights are already reserved for braking, turn signals, headlights, and emergency vehicles.

The color choice attempts to fill a visual gap without causing confusion. While Mercedes-Benz previously won state-level approval for turquoise lights on Level 3 Drive Pilot vehicles, the company later shifted to a Level 2++ system. NHTSA seeks a national standard that companies such as Waymo, Nuro, and Zoox, along with automakers like GM and Mercedes, can adopt consistently.

Under the draft rule, cyan lights would remain optional for manufacturers. However, NHTSA would set federal requirements for their color, brightness, and placement. This approach prevents a patchwork of different colors and signals. Any company choosing to install the lights would use a consistent and legal configuration.

The proposal also removes lighting requirements that rely on human drivers. Current rules mandate physical hazard switches, manual beam shifters, and turn levers inside the vehicle. NHTSA would drop these requirements for driverless designs. The agency also plans to update the 12.8-volt testing standard to accommodate modern LED systems and is considering relaxing rules on high-beam and low-beam light placement.

These changes support a wider Department of Transportation push to accelerate autonomous vehicle deployment. The government aims to ease the path for automakers building cars without traditional controls like steering wheels and pedals. NHTSA continues to enforce existing rules as written. Last month, the agency opened an audit query into the Tesla Cybercab to examine the technical data used for its certification. The review focuses on the absence of sideview mirrors, pedals, and a steering wheel, all of which are currently required by federal standards.