Help with Fog Light Accessories

When it comes to fog light accessories there are two main varieties. First, there is the factory installed equipment and second would be an aftermarket system installed by the vehicle owner. Back when I first started driving factory systems were just about nonexistent. Aftermarket bolt on kits were extremely popular and this was one of the many accessories I installed on my first automobile.Although some motorists consider these additional lights only aesthetically pleasing, they can actually help the driver navigate and see better in foggy conditions. In this article we’ll talk about the usefulness of auxiliary lighting and the theory behind the invention. See the difference between factory mounted fog lights and the similar but different aftermarket versions. Finally we cover a few things to consider when adding additional lights.

Improved Visibility in Fog

Fog lights can actually improve visibility, depending on the situation. The main problem with using any kind of headlamp in foggy conditions is the light is reflected off the water droplets that make up the mist. Instead of the beams penetrating and focusing on the road ahead, they wind up reflecting back at the driver. The idea of a fog lamp is to focus a flat and wide beam of light closer to the ground where less fog may be accumulated. Another advantage of this low mounting location is it provides lighting of the road surface directly in front. This can help make road debris and potholes easier to see.

Factory Installed Fog Light Operation

I have factory fog lights on my personal automobile. The controls are mounted on what Cadillac calls the combination lever. In fact, there’s quite a bit of controls on this lever like the delay wipers, headlight functions, windshield washers and the turn signals. On General Motors vehicles there are a couple of rules or criteria that must be met before the fog light switch will work. This is important because drivers may think the system is broken when it’s not. The Criteria is as follows.The parking lamps must be on which will automatically turn off the daytime running lights. In addition the high beams must be turned off. Therefore, the lights will operate with just the parking lights on or the low beams setting. If you do Select Hi beams the fog lamps will automatically turn off. Some of these rules are actually mandated in certain states to prevent overwhelming oncoming drivers. Another thing to mention is the fog light switch itself is spring-loaded and operates much like the cruise control switch by illuminating an insignia on the dash board indicating the system is on.

Aftermarket Auxiliary Lighting Kits

Buying a fog light kit can provide better reliability and compliance with local laws over individually purchased components because the parts are designed to work together and detailed installation instructions are included. The kits usually come with a relay, switch, all necessary mounting hardware and the lights themselves. The relay is recommended for this circuit because halogen lamps can draw a lot of current. Installing one takes the load off of the switch and the wiring that runs inside the car.

Installing Aftermarket Fog Lights

Generally speaking, the lower the lamp is mounted, the more effective it will be. The goal is to slide a wide beam of focused light underneath the layer of fog. The downside to this mounting location is its vulnerability to road debris and damage from deep snow and water. In these conditions, weather resistant and lenses covered with a stone guard can increase the longevity of the installation.

The other thing to consider when adding any aftermarket accessory is the load it will put on the electrical system, specifically the alternator. Driving lights and fog lamps can require an additional 25 Amps the vehicle was not designed to carry. In short-term situations this is really not an issue, but if these accessories are used often they are capable of damaging the alternator. Forcing it to run at full capacity for long periods of time generates heat that can eventually damage the internal windings and brushes. If the alternator is running full field, to carry the extra load it may not have enough juice to provide a full charge to the battery.