Updated with automaker responses.
The headlights on most small crossovers, among the most popular U.S. vehicles, are inadequate, according to a report published on Tuesday.
The Insurance Institute for Highway Safety, an insurer-funded group, tested 21 small crossover models—and 47 different headlight combinations—and none earned a good rating. Only four of the vehicles received an acceptable rating.
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The bigger problem: More than two-thirds of the headlights were rated poor, and 17 of the small SUVs had headlights with unacceptable glare, according to IIHS.
It’s an industry-wide problem that deserves attention considering about half of traffic deaths occur in the dark or around dawn or dusk, the IIHS argues.
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The price of the vehicle didn’t make a difference, nor did advanced lighting technology in the vehicles. More modern lighting types, including LED lamps, and curve-adaptive systems, which swivel in the direction of steering, also are no guarantee of good performance, according to IIHS.
High-beam assist, which automatically switches between high and low beams based on the presence of other vehicles, was the only type of lighting technology that IIHS deemed valuable.
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IIHS says its rating system doesn’t favor one kind of lighting technology over the other. Instead, its tests focus on the amount of usable light provided by low beams and high beams as vehicles travel on straightaways and curves. Engineers evaluated the headlights using a device that measures how far the light is projected as a vehicle is driven on five approaches: traveling straight, a sharp left curve, a sharp right curve, a gradual left curve and a gradual right curve.
Engineers also measured glare from low beams for oncoming drivers. A vehicle with excessive glare on any of the approaches can’t earn a rating higher than marginal, according to IIHS.
The best-performing headlights in the small SUV group belong to the Mazda CX-3, and are available on this new model’s Grand Touring version. The headlights are curve-adaptive LED lights with optional high beam assist. IIHS says the low beams perform well on both right curves and fairly well on the straightaway and sharp left curve. The group noted that they didn’t provide enough light on the gradual left curve.
The remaining three vehicles with acceptable headlights are the 2017 Ford Escape, Honda CR-V, and the Hyundai Tucson.
The worst—and it’s a long list—includes the Audi Q3, Buick Encore, Chevrolet Trax, Fiat 500X, Honda HR-V, Jeep Patriot, Jeep Renegade, Jeep Wrangler, 2017 Kia Sportage, Mitsubishi Outlander Sport, Nissan Rogue, and the Subaru Forrester.
Fortune contacted several of the automakers mentioned in the study. We’ll update this article if we receive any responses.
Updated: GM didn’t have any comment on the study. An Audi spokesman said its vehicles are all engineered to exceed all federal motor vehicle safety standards as well as to perform to the highest level in tests conducted by IIHS and the National Highway Traffic Safety Administration. In an emailed statement, the company added that it is committed to building the safest vehicles available to the public and takes evaluations from IIHS very seriously. Audi says it will carefully review the methodology and the results.
A Fiat Chrysler Automobiles spokesman said in an emailed statement that the car company continually evaluates the safety performance of its vehicles and that all meet or exceed all applicable federal motor-vehicle safety standards.
“No single test determines overall, real-world vehicle safety. And there are multiple ways to evaluate headlamps,” FCA says in the statement.
Consumer Reports also rated headlights on car models this year, and notes how its tests are different from IIHS. Some vehicles, such as the Jeep Patriot fare better in the Consumer Reports reviews.
IIHS warns that manufacturers don’t pay enough attention to actual on-road performance of headlights—instead relying on laboratory tests. And since government standards are based on these lab tests, there’s little incentive for automakers to do more real-world testing of this piece of equipment.
Updated with automaker responses at 2:40 p.m. ET.