I am about to install fog lights in my 99 Sierra but it did not have fog lights from the factory. Are the plugs in the factory harness still? Also it the plug for the facotry switch behind the dash? If not how do I go about wiring them in?--Tony

 

what i found on my 02 is that there is a factory spot in the fuse box under the hood for the fog light relay, if you have a relay that will fit wire it in there. if you dont, like i didnt, then run your own relay and tap into the low beam power wire (either side) then run your ground. this way the fog lights will come on with your headlights.

if you want them to come on via toggle switch then just run either the power or ground wire through the toggle to turn them on and off.

i ran mine off the headlights and ran a relay bc the wire going to the headlights is only 20ga. and i didnt want it to support my headlight and two additional fog lights without the help of a relay.

if you dont have a relay then you can run one fog light off of each headlight to lighten the load so to speak but i would recommend running it through a relay if you have one. they are not real expensive to buy at a local parts store.

 

I do have the spot in the fuse box for a relay, I am going to check tonight and see if the plugs are in the factory harness or not. If they are, do I just have to put a relay in, buy a factory fog light switch and plug it all in?--Tony

 

On my 02 silvy, the kit came with the wiring that you run from the fog lights to the fuse box. If I remember correctly, the wiring from the fuse box to the switch was already there. When you put in the factory switch the wiring is there and you plug it to the switch.

Also, you will more than likely have to have the BCM reprogrammed to get the fog lights to work, I did as well as many others.

 

might as well just tap in to the low beams it would be the easiest way to have them turn on and off with the lights that way you dont have to worry about getting teh BCM programmed

 

or tap into ure parking lights

 

Tony get ahold of me man, I had to do this on my old silverado. I can help you out bro.

 

I don't have your number anymore man, shoot me a PM with it. Or when is the next time you will be at the shop?--Tony