As it comes from the factory, you can not run your high beam headlights and your fog lights at the same time. I would assume that it is some sort of federal mandate that you can't have this much light on at one time. I always run with my fog lights on at night and was upset that they went off every time I turned on my high beams. So, after searching the internet I found out how to modify my Jeep so that the fogs would stay on no matter what setting my headlights were at. But like I said, this may be some sort of federal law or something so I will accept no responsibility for what you do.

Do this mod at your own risk!

I had heard about this modification before but had a lot of trouble finding out how to do it. Once I did manage to find some information it was for an earlier model and not for my 2003 TJ. I put a little thought into and, with some luck, figured out how to make it work. From what I can tell, all years are the same with the exception of the numbers printed on the relay.

If it takes you longer than two minutes to do this mod you need to stop because you are doing something wrong.
The first thing you need to do is pop the hood. If you look on the passenger side of the Jeep, just in front of the battery, you will see a black box.

Just pop the cover off the box and pull out the headlight relay. It is the one circled in the picture.

If you flip it over you will see several prongs sticking out of the relay.

The prongs are numbered but I will not include the numbers here as this is the part that screwed me up when I learned about this. I learned how to do this from a '97 TJ (I think) and it was numbered one way, but the numbers were different on my '03 model. I had to take a guess as to whether I needed to follow the numbers or the pictures and, luckily, I chose right. So, to make it easier on everyone, I will just include a picture to follow.

Just look at the picture and bend over the prong that I have. Some people break it off and I have heard of some people putting some sort of coating on it so that it will not make electrical contact. This is extra work and it works just fine bent over.

Just reinstall everything and you're good to go.

I don't know anything about how this affects anything in the Jeep but I have had no problems with it and do not expect to. But, just to protect my ass I will say again they you are doing this at your own risk.

I hope this helps someone and I am able to give back a little of the help that I have received.


If you have any information about years other than mine or have anything that you would like me to add, then feel free to email me.

email me at mail@davenjeip.net

Also, here is the link to the site I used to do this. It has since been updated and may provide you with more information than I have

Home

Back to Tech