NHTSA Standardizes Cyan Lights for Driverless Cars

Driverless vehicles could soon feature a specific blue-green glow to signal their status to surrounding traffic. The National Highway Traffic Safety Administration has proposed a national standard for cyan marker lamps. This change would give law enforcement and other road users a clear visual cue that an automated driving system is in control.

The proposal amends Federal Motor Vehicle Safety Standard No. 108. NHTSA aims to create a consistent visual language for autonomous fleets. Companies such as Waymo, Nuro, and Zoox, along with automakers like GM and Mercedes, could adopt the same configuration. The agency notes that red, amber, white, and flashing lights are already reserved for braking, turn signals, and emergency use. Cyan fills a visual gap without causing confusion.

Mercedes-Benz previously received state-level approval for turquoise lights on its Level 3 Drive Pilot vehicles. The automaker has since shifted to a Level 2++ system. Despite that shift, NHTSA wants a federal standard to prevent a patchwork of different colors and signals across the country.

The cyan lights would remain optional for manufacturers. However, any company that chooses to install them must follow federal rules for color, brightness, and placement. This approach ensures a uniform appearance regardless of the vehicle make or model.

The agency is also removing lighting requirements that do not apply to vehicles without human drivers. The proposal eliminates the need for physical hazard switches, manual beam shifters, and turn levers. It also updates the 12.8-volt testing standard to accommodate modern LED systems. NHTSA is considering dropping rules that dictate the position of high-beam lights relative to low-beam lights.

These changes align with a broader Department of Transportation effort to speed up the deployment of autonomous vehicles. The goal is to ease regulatory burdens for designs that lack traditional human controls. Regulators are currently enforcing existing rules as written. Last month, NHTSA opened an audit query into the Tesla Cybercab. The agency is examining the technical data Tesla used to certify the vehicle, specifically regarding the absence of sideview mirrors, pedals, and a steering wheel.