The National Highway Traffic Safety Administration (NHTSA) has released proposed changes to Federal Motor Vehicle Safety Standard (FMVSS) No. 108, introducing a specific color requirement for autonomous vehicles. The agency wants driverless cars to use cyan marker lamps to signal to other road users and law enforcement that the vehicle is operating without a human driver.
Standardizing Autonomous Signals
For years, the debate over how self-driving cars should communicate their status has been open-ended. Proposals have ranged from flashing text displays to audio alerts and custom light patterns. The NHTSA has now stepped in with a single, standardized answer: cyan.
The agency states that cyan marker lamps will “clearly and consistently signal to law enforcement and other road users when an automated driving system is operating the vehicle.” The choice of color is deliberate. The automotive industry already utilizes red, amber, white, and flashing blue or red lights for brakes, turn signals, headlights, and emergency vehicles. Cyan fills a visual gap in the spectrum, reducing the chance of confusion for pedestrians and other drivers.
There is some precedent for this approach. Mercedes-Benz previously received state-level approval for turquoise lights on its Level 3 Drive Pilot cars, although the automaker later scrapped the feature in favor of a Level 2++ system. The NHTSA aims to establish a national standard that robotaxi operators like Waymo, Nuro, and Zoox, as well as major automakers such as GM and Mercedes, can adopt uniformly.
Updating FMVSS 108 for Modern Designs
Under the proposed rule, the use of cyan marker lights would be optional for manufacturers. However, by defining the color, brightness, and location of these lights, the NHTSA intends to prevent a confusing mix of non-standard signals. Any automaker choosing to add them would follow a consistent, legal setup.
The proposal also seeks to remove lighting and control requirements that are irrelevant for vehicles without human operators. Current regulations mandate physical hazard switches, manual beam shifters, and turn levers inside the cabin. The NHTSA proposes eliminating these requirements, allowing manufacturers to design interiors without traditional controls.
Additionally, the agency is updating the 12.8-volt testing standard. This change is designed to accommodate modern LED architectures, reducing administrative burdens for automakers. The NHTSA is also considering removing rules that dictate whether high-beam lights must be positioned above or below low-beam lights.
This regulatory shift aligns with the broader Department of Transportation strategy to streamline autonomous vehicle deployment. The goal is to make it easier for companies to build cars that lack steering wheels and pedals. However, enforcement remains strict for those who bypass existing rules. Last month, the NHTSA opened an audit query into the Tesla Cybercab to examine the technical data used to certify the vehicle, specifically regarding the absence of sideview mirrors, pedals, and a steering wheel.
Source: The Verge
