I know there are already articles about this, but I am offering another solution that I have not seen in the forums. I have been running my 2003 TJ this way without any problems. With this, I will add the following disclaimer:
in some states it may be illegal having high-beams and fog lights concurrently operating. This conversion is intended for off-road use only. However, if you don't leave both high-beams and fog lights to blind oncoming traffic, you should be fine. It is my belief that this decision should be left up to me and not be decided for me by the manufacturer and/or the government.
The way I see it, I know what the speed limit is but the automakers donít install a speed control device in my vehicle that will never allow me to break the speed limit, so they should have no control of how I run my lights. With that said, making a permanent conversion to your jeep may cause it to not pass inspection. My method is not permanent and can be changed back and forth in a matter of seconds for when it comes time for your state inspection.
First I will show you what the current permanent method is that can only be reversed by changing the fog light relay with a new one.
To get started, you will need to locate the fog light relay in the fuse box next to the battery. Pull the fog light relay and you will notice it is a five pin plug. See photo below
From the view on this picture, on the top row where there are three pins, you will need to bend the far left pin over and around the side of the relay switch. See the next two photos
After doing this, you simply plug the relay back in and you can now run your fog lamps with your high beam lights. The problem with this fix is that it is a permanent solution to this relay switch. If you try to straighten the pin back it will break. Why is this a problem? First the relay switch will not fully seat back into the fuse box. Plus, when you go to have your vehicle inspected it will fail inspection because the high beam to fog lamp cutoff has been disengaged. The only way to resolve this is to have an extra relay switch on hand to change out before you take it to get inspected.
Now for my simple non-permanent solution. You will follow the steps above except you will not bend the pin. The relay switch will actually stay intact. You will however add a plastic sleeve to the same pin.
To explain, I work in law enforcement so I have often times had to take offense reports from the electric company in reference to individuals who have had their electricity turned off but they have illegally turned it back on. When the electric company doesnít completely pull their meter to disconnect the electricity, they simply slide on plastic disconnect sleeves to the meter pins so that there is no conductivity to allow electricity to flow through the meter and into the house. This can be done with your fog light relay too, but we will have to make our own since those used by the electric company are too big and may not be available commercially. The photo below is the meter disconnect sleeves used by electric companies.
To make our own, first you will need some type of plastic material. The type I use is the clear plastic that is usually on packaging such as toys which allows you to see the contents of the box. See photo below
You will need to cut a piece of this plastic the exact width of the pin to make a sleeve that will go over both sides of the pin. As far as the length of the sleeve, cut one side so that it will be flush with the top of the relay switch on the side of the pin that will immediately have a pin next to it. On the side of the pin that faces the outside wall of the relay switch, you will want the length of the plastic to be longer. Iíll explain below, but see photo for examples.
After you do this, you will plug the relay back into the fuse box. It will be a snug fit but be sure and seat the relay switch in its full resting or plugged in position. As you will see in the picture below the plastic tab that was left longer on the outside of the relay switch will prevent the plastic sleeve from becoming stuck in the fuse box slot. You will hold on to this part of the plastic sleeve when you need to remove the fog light relay in the future.
Now you can run your fog lamps with your high beams for your entire off road needs. When itís time for inspection, you will have no need to have an extra relay switch that will inevitable get lost over the year span of your inspection, you simply pull the relay switch, remove the sleeve and reinstall the relay for inspection. Afterwards, you reinstall the plastic sleeve and youíre back up and running in a matter of seconds. Hope this helps someone!