Some headlights are not very bright

Headlights coming under increased scrutiny for contribution to safety


Headlights are coming under increased scrutiny for their contribution to safety

As someone who drives hundreds of new vehicles every year, I am well aware of the disparity in headlight performances. Part of my normal test route involves unlit secondary or back roads. It only takes a moment in these conditions to recognize a good set of headlights – or poor ones. IIHS tests are more conclusive – and damning.

The Insurance Institute for Highway Safety (IIHS) tests more vehicles than I do – by a wide margin. It conducts these tests scientifically and accurately and has started testing headlights and including the results in their overall safety ratings.

These ratings by the Washington-based non-profit, independent IIHS focus on overall safety. They are widely respected by the industry and much sought after by vehicles manufacturers. The ratings are based on Passive Safety – how well a vehicle protects occupants in a crash and Active Safety – features that help prevent a crash or lessen its severity.

IIHS “Safety Pick” ratings now include headights

The IIHS is now including headlight tests in the ratings. These tests are conducted as the vehicle travels straight ahead and on curves. Sensors measure how far the light travels “with an intensity of at least 5 lux”. Lux is a unit that measure how much light falls on a surface. IIHS says for comparison purposes, a full moon on clear night illuminates the ground to about one lux.

Both high and low beams are measured under five situations – straight, gradual left and right and sharp full left and right turns. Glare to oncoming vehicles from low beams is also measured and factored into the rating.

Test results have been pretty disparaging for some vehicles and manufacturers.

The first batch of results were pretty disparaging for some vehicles and manufacturers. How much weight the ratings carry is evident in that the headlights of many of the vehicles that received a “poor” headlight rating, have already been updated and improved.

So far, the IIHS has released four group studies. The results indicate the headlights on most new vehicles are not very good. “Poor” or “marginal” ratings have been given to foreign and domestic vehicles at all price points.

40% of vehicle headlights receive a “poor” rating

Only four of the first 100 vehicles tested, received a “good” headlight rating and 40 a “poor” rating. For example, the IIHS has given a ‘good’ headlight rating to only two of 37 midsize SUVs tested. As a result of having the headlight ratings incorporated into the overall safety rating, only 15 of the vehicles have received the IIHS 2018 “Top Safety Pick Plus” rating, compared to 38 for the 2017 model year.

Click here to see the ratings for mid-size cars.

Click here to see those for small SUVs

The majority of headlights use one of three different light sources: halogen, high-intensity discharge (HID) or LED. Each system is paired with either reflectors or projector lenses. Reflectors bounce the light forward from multiple surfaces. Projectors use a single lens to broadcast the light forward, while reflectors have multiple surfaces that bounce the light forward. Most of the good- and acceptable-rated headlight systems have HID-sourced light and projector lenses. The IIHS points out, that “having HIDs and/or projector lenses doesn’t guarantee good or acceptable performance”.

The majority of headlights use one of three different light sources

The most recent development in headlight systems is the use of LEDs (Light Emitting Diodes). As prices from suppliers tumble, they are becoming increasingly common.

The next advancement becoming common in Europe, but not yet permitted in North America, is adaptive lighting. These systems allow the use of high beams, even in the face of oncoming traffic, by shutting down that portion of the light that would otherwise shine into oncoming vehicles. I have tried these, and they are nothing less than amazing!

Another advance mandatory in Europe but not by our dated regulations, is the requirement for self-levelling headlights. This ensures headlights remain properly aimed, even if a heavy load causes the rear of a vehicle to drop, and the front to rise.

Regulations are outdated

Existing federal regulation in Canada and the US covers headlight beams, and set limits for maximum and minimum intensity. The IIHS says this is not enough. It says the rules do not cover aim, and that vehicles often come off the assembly line with poorly aimed lights. “This can cause glare, and renders the move to brighter LEDs null,” the IIHS says.

Next – ratings for mid-size cars

About Richard 166 Articles
At the age of five I was already obsessed with all things automotive being able to identify the make and model of car by just the sound of its engine going down the street in front of our house in the small town on the south shore of Nova Scotia. Although I have been covering and writing about the automotive scene for more than 40 years and the light still grows brightly.