NHTSA and China Both Propose Optional Colour Lamps for Self-Driving Cars

The US National Highway Traffic Safety Administration has proposed an optional cyan marker lamp that would light whenever a car is driving itself, Electrek reported on Oct. 24, four days after China's industry ministry opened a consultation on the same idea in turquoise. Neither country would require the lamp.

NHTSA's press release and the draft rule's PDF could not be retrieved (both returned HTTP 403), so the US details below rest on Electrek's reading of the draft. The Chinese details come from CnEVPost, whose founder and editor-in-chief is Phate Zhang.

What the US draft says

The proposal sits in docket NHTSA-2026-1519 and amends Federal Motor Vehicle Safety Standard 108, the lighting rule. Per Electrek, it would allow cyan marker lamps on the front, sides and rear, at least 15 inches off the ground, visible from any angle. They would switch on when the automated system is driving and off when it is not, never while a human drives, and every lamp would change state at the same moment.

Electrek says the same draft removes the turn-signal auto-cancel requirement for cars without steering wheels and changes some headlight requirements. It says the rule will be open for 30 days on regulations.gov but gives no opening or closing date. It also gives no wavelength for cyan, which matters because a lamp colour is a chromaticity box in the regulation, not a word.

Electrek credits Mercedes-Benz with the idea, which the carmaker first used with its DRIVE PILOT Level 3 system and trialled in California for two years. Electrek says SAE International, the standards body, also favours cyan and gave input.

What China's draft says

China's Ministry of Industry and Information Technology opened its public consultation on Oct. 20, and comments close Dec. 19. The draft is one of five mandatory national standards on external lighting. It reserves turquoise for vehicles with Level 3 or higher automated driving, makes fitting optional, and bars the driver from switching the lamps manually.

The recommended effective date is Jan. 1, 2028, with transition periods of up to 48 months for some provisions. The draft also bans lamps that display text or form faces, exempts illuminated logos, and bans voice commands that turn lights off.

CnEVPost links the draft to July reports that the ministry had told carmakers to stop using unofficial "little blue lights" on driver-assistance cars. Yicai, citing an automaker insider, said newly certified models had been barred from such lamps since July 27, though the ministry issued no public document.

	United States (draft)	China (draft)
Colour	Cyan	Turquoise
Required?	Optional	Optional
Automation level	Not specified in Electrek	Level 3 and above
Timing	30-day comment period	Comments close Dec. 19; effective Jan. 1, 2028 recommended

What a shared colour would and would not settle

The agreement on optional fitting is the real alignment. A mandatory lamp would force every automated vehicle to carry added hardware. An optional one lets Mercedes and Chinese makers fit it while everyone else waits.

The unresolved variable is the colour tolerance. If NHTSA's cyan and the ministry's turquoise sit in overlapping chromaticity regions, one lamp unit could serve both markets; if they do not, an exporter carries two part numbers. Neither source gives the numbers, so that question stays open until the draft texts are read.

The next dates are fixed. China's window shuts on Dec. 19, and the US docket should show comments once regulations.gov posts it. If the final NHTSA text ends up mandatory rather than optional, the cost case changes entirely, and that would be the signal to revisit this read. Electrek's own view is that the rule was "a long time coming" but needs monitoring as requirements for vehicles without driver controls loosen. For other robotics policy moves, see The Terminal's coverage of the FCC covered list and of Dream Labs' robot API.