Compounding the problem of driving with deteriorated headlights is the fact that U.S. headlights have significant shortcomings. Previous AAA research found that halogen headlights fail to safely illuminate unlit roadways at speeds as low as 40 mph, with high beam settings offering only marginal improvements. Even the most advanced headlights tested illuminated just 40 percent of the sight distances that the full light of day provides. By not maintaining headlights, drivers are unknowingly operating in dangerously dim conditions.
“Driving at night with headlights that produce only 20 percent of the light they did when new, which is already subpar, is a risk drivers shouldn’t take,” continued Brannon. “Especially when there are convenient and inexpensive solutions that can dramatically improve lighting performance.”
Most headlights are made of plastic and exposure to sunlight breaks down the plastic coating, causing discoloration that obscures the amount of light produced. Depending on where and how the vehicle is used, headlights can begin showing signs of deterioration as early as three years to five years.
Unlike batteries or tires, most drivers are not in the habit of routinely inspecting their headlights. AAA suggests drivers check their headlights for changes in appearance such as yellowing or clouding and if the bulb is difficult to see, it is time to have the lenses replaced or restored as soon as possible. AAA recommends replacement since this method offers the most improvement in the amount of light produced. Both replacement and restoration services are provided by many repair shops including many AAA Approved Auto Repair facilities.
Headlight assemblies used in testing were for the left (driver’s) side of the vehicle. To quantify headlight performance, AAA contracted an accredited testing laboratory with expertise in automotive headlights and conducted testing according to industry standards. Headlights were tested according to FMVSS-108 standards with no modifications to the headlight assemblies under test or to the test procedures.
The professional headlight restoration systems used a power sanding technique to remove the original protective film from the headlight lens. The resulting scratched surface of the polycarbonate was then polished using increasingly finer grades of sanding discs and a protectant film applied to the entire surface of the headlight lens. Full methodology available in the research report found here.