Adaptive headlights, also known as adaptive front lighting systems (AFS), are an advanced headlight technology that aims the headlights in the direction the driver steers the vehicle. This provides improved visibility and safety compared to traditional fixed headlights. Adaptive headlights are common in Europe, but the legality in the US has been unclear. This article examines if adaptive headlights are street legal in the United States.
What are adaptive headlights?
Adaptive headlights use a variety of methods to adjust the aim of the headlight beams based on driving conditions. Some common adaptive headlight functions include:
- Steering-linked headlights: The headlights move in the direction the driver steers the vehicle. This provides extra illumination in curves and turns.
- Curve lighting: The headlights can swivel horizontally to increase side illumination when cornering.
- High beam assist: The high beam automatically turns on and off based on the presence of other vehicles.
- Adverse weather lighting: The headlights optimize the light pattern for rain, snow, and fog.
These adaptive functions improve visibility significantly compared to traditional static headlights. Studies by the National Highway Traffic Safety Administration (NHTSA) found that steering-linked headlights can improve illumination by up to 15%.
Are adaptive headlights legal in the US?
The legality of adaptive headlights in the US has been murky for years. Historically, the 1968 Federal Motor Vehicle Safety Standard 108 effectively banned complex headlight systems like adaptive headlights. However, the NHTSA amended this standard in 2006 to permit advanced headlighting systems like adaptive headlights. But each adaptive headlight design still requires specific NHTSA approval to be legal for use on US roads.
As of September 2023, several car manufacturers have NHTSA approval for adaptive headlight systems in the US market. Mercedes was the first in 2012 with approval for their Adaptive Highbeam Assist. Audi, BMW, Mazda, Volkswagen, and Volvo also have NHTSA-approved systems available in US models today.
So in summary – yes, adaptive headlights are legal in the US as long as the specific headlight system has NHTSA approval. The technology is still making its way into the US car market, with more automakers gaining approval each year.
Are there restrictions on adaptive headlights in the US?
The NHTSA approvals for adaptive headlights do come with some restrictions and requirements:
- Beam switching speed cannot exceed 0.3 seconds
- Headlights must switch to low beam when facing oncoming vehicles
- Maximum luminance values cannot be exceeded
- Headlight movement range is limited
- Systems must automatically level headlights
Additionally, some state laws restrict the use of adaptive headlights or require them to be disabled:
| State | Adaptive Headlight Restrictions |
|---|---|
| Massachusetts | Use of adaptive headlights is prohibited |
| South Dakota | Adaptive headlights must be disabled when vehicle registered |
| Minnesota | Adaptive headlights restricted to 5 degrees maximum swivel |
So adaptive headlights cannot be used in Massachusetts at all. Other states have partial restrictions, but most have no issues with adaptive headlights being used.
What cars have adaptive headlights in the US?
Here are some examples of cars currently available in the US market with NHTSA-approved adaptive headlights:
| Make | Model | Headlight System Name |
|---|---|---|
| Audi | A4, A5, A6, A7, A8, Q5, Q7 | Audi Matrix LED headlights |
| BMW | 2 Series, 3 Series, 5 Series, 7 Series, X5, X6 | BMW Selective Beam |
| Mazda | CX-5, CX-9 | Mazda Adapive LED headlights |
| Mercedes | C-Class, E-Class, S-Class coupe | Mercedes MULITBEAM LED |
| Volvo | S60, S90, V60, XC40, XC60 | Volvo Active High Beam |
Many other automakers like Acura, Cadillac, Lexus and Porsche also offer adaptive headlights on some models in the US or have systems awaiting NHTSA approval.
Are adaptive headlights worth it?
Adaptive headlights provide proven safety and visibility benefits, but are they worth the extra cost? Here are some pros and cons to consider:
Pros of adaptive headlights:
- Greatly improved night time visibility in curves, turns and hills
- Automatic high beam dimming reduces glare for other drivers
- Safer driving and obstacle detection
- Reduced driver fatigue on long night drives
- Cool tech factor
Cons of adaptive headlights:
- Expensive option costing $1000+ on most vehicles
- Minor ongoing reliability/maintenance concerns
- Limited availability – only luxury brands offer currently
- Marginal benefits for city/suburban driving
Overall, many reviews find adaptive headlights provide substantial benefits for night time and rural driving, especially on curvy roads. But the cost may only be worthwhile if doing a lot of night driving in low visibility conditions or want the latest technology.
The future of adaptive headlights
Adaptive headlights are still an emerging technology in the US, despite wide use in Europe for over a decade. Regulatory approval has been the primary hurdle, but the NHTSA and automakers continue cooperating to bring the safety benefits of adaptive headlights to the American market. Availability is steadily increasing each model year as more automakers gain NHTSA approval. Many industry experts expect adaptive headlights to become standard equipment on most models by the late 2020s.
Automakers are also developing more advanced capabilities using improved camera, radar, and communication systems. For example, Audi, Mercedes and others are working on digitally connected headlights that can share real-time data and adjust to hazards automatically. These connected and collaborative headlights could make night driving much safer in the future.
Conclusion
Adaptive headlights are legal in the US as long as the specific headlight system is approved by the NHTSA. Mercedes started offering the first adaptive headlights in 2012, with BMW, Audi, Mazda, and others now also providing NHTSA-approved systems. Availability in the US car market is increasing rapidly. Adaptive headlights can significantly improve night vision around curves and turns. They provide proven safety benefits but remain a luxury option due to high cost. As technology improves, adaptive headlights are poised to become standard equipment across most vehicle segments in coming years.
