The purpose of fog lights is to provide light down low, under the usual
(headlight) height of fog. They should be used when headlights are off.
It's because if you run headlights, especially high beams in fog, they
tend to blind the driver due to light reflecting back from the fog.
Using fog lights together with high beams is ass-backwards, you negate
the benefits of fog lights by using high beams to still blind you.
Running fog lights when there is NO fog, creates a bright spot on the
road right infront of the driver, sometimes effectively drawing
attention from where you SHOULD be looking at - further down the road.
It also can blind you a little, your eyes adjust to the bright spot and
you don't see what is going on immediately outside of it (pedestrians,
animals, etc just outside of the beam) - your night vision suffers!
Personally, I have found fog lights to be the most useless kind of
lights imaginable on a car. The number of times I have really needed
them are very very limited.
In certain regions, it is illegal to have fog lights on unless there is
fog present. You get fined. That probably stems from the habit many
people have of aiming them too high to supplement their weak headlights
under normal driving conditions, and that's when they blind the oncoming
Now, if you just wanted them on for the cool factor, you can achieve
that with a separate power source and a switch on the dashboard or
center console, or you can install a relay that draws signal power (very
weak) off of some power source that suits your need. The high beam
indicator light would work well if you ONLY wanted them to come on with
your high beams. Or steal the signal from the high beam bulb wire
itself. Still, be warned that this might actually hurt your vision in
the dark because of the bright spot right in front of the car that makes
your eyes adjust for bright instead of dark.
The "Fog Lights" as Ford still calls them are not positioned correctly
2005-on Mustang to function properly as fog lights. The various models
1979 to 2004 which included fog lamps were all placed very low below
The new car's placement in the grille between the headlights seems to
the early '70s Mach 1 "Sport Lamps".
PS - I really hate rude, inconsiderate oncoming drivers who don't dim
brights/foglights/landing-lights. Is it just my area of the country
think it's cool to try and blind people at night ?
Even though the fog lights on my 2006 GT are in the grill above the bumper,
they still shine down sharply, and are wide angled, like traditional fog
lights. They don't have to be mounted low on the front of the car to be
That is why most cars today don't even use "fog lights" any more, they use
"driving lights" IE; Mustang GT, these are basically a second headlight
bulb, not a fog light.
If you want to drop just over $100 on a solution, to run all your lights,
lowbeam, highbeam and driving lights at the same time, same as flash to
pass, but don't want to burn out your light switch or wiring, look into a
Bright Box light box.
ISTR that it is illegal to have more than 4 (2x2) lights on concurrently,
on the front of a car. So, high-beams + low-beams + fogs is a no-no.
I looked in the current MA driver's manual, but it has been dumbed down
a lot, and a lot of info has been removed.
Brite Box Manufacturer
Baker Auto Accessories
1250 So, Lincoln Ave.
Steamboat Springs, CO 80488
And if todays cars actually had "fog lights" that would be true, but
using Daniels Sterns term to describe todays substitute for fog lights
the sick jokes that are used are good for nothing more than looks anyway.
"Wow, I want a billion Dollars and a pet monkey!" - Dale Jarrett
Point was, people often point them too high because they find out they
don't help much at all if aimed properly for fog.
So they aim them higher. They end up with crappy 'helper' low beams that
blind oncoming traffic.
The point is they are totally worthless when used on clear nights,
especially inside a city. They are just an unnecessary distraction. While
the low mounted ones aren't too bad, the ones mounted up higher, especially
in SUVs and pickups are high enough that they are aimed directly in the rear
window of many smaller vehicles.
There is absolutely no valid reason for using "Fog Lights" on a clear night
when in traffic. Using "Fog Lights" in heavy traffic on lighted city streets
identifies the vehicle driver as an inconsiderate jerk.
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