GM Truck Club Forum banner
1 - 2 of 2 Posts

1 Posts
Discussion Starter · #1 ·
Hello I just got a 2005 2500HD pickup but it didn't come with fog lights and I would like to install some factory fog lights. I can't see this really being a problem i've done stuff like this before but I wanted to see if anybody had any insight on it before I just jump in on the project.


163 Posts
I put the GM kit in my 05 1500 and it was not too hard if you are used to working on a vehicle. If you are talking about using the GM kit to make it a factory install be advised( assuming the 2500 lights are the same as the 1500's )it does involve getting to the underside of your fuse panel and to the wiring harnesses there. Also, the directions that come with the kit for the 03+ fog's have some errors in regards to locations to put things( ie; relay and also the wiring harness pin location ). You can check out this thread here on another site I replied to where I helped someone else with the wiring. Unfortunately, the photos no longer show I had for referrence as I deleted them from my photobucket album and I no longer have them to repost for you. Still, it will help you out.

If it is a different kit/lights for the 2500 then ignore the following. If they are the same this is basically what you have to do...

1 - remove the bumper valance and replace it with the one in the kit. There are a bunch of push pin type clips along the front that need the center pried out. On each end you have 2 bolts that need to be removed then the valance comes off with a little tugging. Make sure you line up the new valance before snugging the bolts down on each end or you will have gaps.

2 - Mount the fog lights themselves. Not hard but it is awkward getting the bolts started. While you are down there you can look to see if the truck came prewired for fogs. My truck didn't have fogs from the factory but was prewired for them. Saves a LOT of hassle if it is prewired. If you check the link above my 1st reply in the post tells how to find out if your truck is prewired.

3 - Next you go in the cab to replace the switch. The front face trim plate just pops off which exposes the cargo light switch. That also just pops out but but be advised you have to pop the whole housing it is in out to be able to release the clips that hold it in top and bottom( I think the housing just pops out as well - can't remember 100% for sure there aren't any bolts/screws but I don't think so - maybe? ) . It is quite a PITA to get the switch itself out of the housing as both the top and bottom need to be released AT THE SAME TIME before the switch will slide out. Like trying to catch a greased pig on ice. The plug is the same regardless of whether or not you had factory fogs so just plug the new combo switch( cargo & fog )in and pop it into the housing then pop the whole housing back in. Snap your face plate back on and you are good to go in the cab.

4 - under the hood you need to remove the fuse box cover and install the fog lamp relay. Direction picture is wrong but it can only go one place( any I have looked at anyway ) so no huge deal.

5 - now here is the most difficult part of it all unless you are prewired for fogs. If you are just plug them in now and you are done. If you are not prewired then there is more to it. You have to remove the fender brace and then unbolt, and unhook power to, the top of the fuse panel so it will tip up so you can get to the wiring underneath. The directions given oonce again show the wrong location to insert one of the parts. This time it is the wiring harness. The link above tells you the proper location( top row, 3rd from left as I recall, but it is right next to a red wire so no missing it ). You have to remove the headlamp harness from the underside of the fuse panel to do it. After the harness is installed button it all back up.

You are done after that except for routing the harness to the lights and plugging it in( you also have to drill a hole in the frame to allow a ground wire to be attached ). In some cases the trucks Body Control Module( BCM )needs to be programmed to recognize the fog lights and allow them to turn on. Most times however they work plug and play.

Overall it is not that hard but it is time consuming the 1st time you do it. I could do it in a fraction of the time now that I have done it once. The worst part is actually changing the valance over, mounting the lights, and running the harness because you are on your back on the ground( much easier on a lift if you have access ).

Hope this helps and if you get the kit and have questions feel free to ask. Will help if I can. Again, just keep in mind the above is for the 1500. Not sure if the 2500 is the same.
1 - 2 of 2 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.