Q. - Fog lights are one of my pet peeves. When a big SUV comes at you, it is quite a feat to stay on the road. Flashing doesn't help. Can you? – John in Milton, Ont.
Q. - It would appear that the rules on headlights are not practical for police enforcement. Is there any chance of our adopting the European practice of automatic light-leveling systems? In my experience, many oncoming vehicles use fog lights along with headlights regardless of the weather conditions, thereby adding to the glare effect. Another unenforcable situation? – Rob
The vast majority of "fog lights" we see on vehicles today are useless affectations, secondary light sources that accomplish nothing other than creating this type of reaction for those in oncoming vehicles.
There is a secondary problem when they are used by tall vehicles like SUVs and pickups – the height of the light source. Ironically, this makes them even more useless in fog.
Fog lights were originally intended for use in heavy fog, snow, rain and other situations where visibility is restricted. A proper fog light is designed to have an extremely sharp cutoff at the top to prevent light from reflecting off the water droplets or snow that is causing the problem.
We have all experienced what happens when light reflects off in this manner when you put your high beams on while driving through heavy rain, snow or fog – the resulting reflection is blinding, causing us to switch back to low beams, which have a cutoff at the top to prevent the light going into oncoming vehicles. For this reason, proper fog lights have a sharp cutoff at the top of the light and are designed to be mounted very low on the vehicle and project a wide light under the rain, fog, snow, etc.
The light from a proper fog light will not appear more than 5 to 10 cm off the surface of the road. Once designers started using "fog" lights as jewellery on the front of a vehicle, and drivers decided to use them to show off their purchase, the problem began.
Now we have a raft of vehicles driving around with these useless lights aglow day and night, in bright sunshine, clear, dark nights and making visibility worse in fog or other situations of restricted vision.
Granted, some high-end European vehicles have proper fog lights, but since they are properly designed to restrict their light path to a low level, they are not a problem for oncoming motorists. The rest, the vast majority, serve no purpose other than to display the driver doesn't know what he or she is doing.
This is compounded when the "fog" lights are used on a tall vehicle. The lights are already too far off the ground to be useful as a fog light and, in most cases, do not have a cutoff of any nature since they are mere jewellery. So, here we have light sources that shine directly into the windshield, rear window or mirrors of other vehicles.
The answer, in my opinion, is regulations requiring an annual vehicle inspection for all passenger vehicles that involves checking headlights and "fog" lights for proper operation and aim. And while they are at it, mandate that daytime running lights be separate from instrument panel lighting and that automatic headlights be mandatory on all vehicles.
Send your automotive maintenance and repair questions to email@example.com.