Ask a Trooper: Driver is blinded by the fog lights
Question: I see a lot of people who have their fog lights on when I am meeting them on the road. Some are very bright and make seeing the road very difficult. Some of them appear to be out of alignment and are blinding. What is the law that covers this?
Answer: There are some specific requirements for those lights, but if the fog lights are aimed too high and/or are too bright then they are not legal just for that reason, even if they are in compliance with the rest of the law. All lights for vehicles have to be approved by the Commissioner of Public Safety and they have to be allowed by statute.
Minnesota law says that any motor vehicle may be equipped with not to exceed two fog lamps mounted on the front at a height not less than 12 inches nor more than 30 inches above the level surface upon which the vehicle stands and so aimed that when the vehicle is not loaded none of the high-intensity portion of the light to the left of the center of the vehicle shall at a distance of 25 feet ahead project higher than a level of four inches below the level of the center of the lamp from which it comes.
Lighted fog lamps meeting the above requirements may be used with lower headlamp beams.
Another relevant law says that when a motor vehicle equipped with headlamps, as (herein) required, is also equipped with any auxiliary lamps, spot lamps or any other lamps on the front thereof projecting a beam of intensity greater than 300-candle power, not more than a total of four of any such lamps on the front of a vehicle shall be lighted at any one time when upon a highway.
The best practice is to keep your lights on at all times on the road to make yourself more visible to other drivers. It’s the law to have head lights (and tail lights) on during rain/snow and when visibility is reduced.
Anytime your vehicle’s height is altered, by adding larger tires/rims or any type of suspension lift, your headlights and fog lights may need to be adjusted so they are not blinding to other motorists.