Did a search for info - got a diagram of the fuse block - still don't see anything that tells me where the power source fuse or relay is located for my factory fogs that aren't working. Anyone know what fuse or relay controls these on an '89??

 

A word of caution before I answer this. I am having the same problem so take anything I say with a grain of salt.

I have an 87 MJ with factory fog lights and the relay on it is located in the engine bay along the driver side toward the front. You can see a wiring harness running along the side and into the front grill. A ground splits off from there. Next to that is the relay.

When you turn on your headlights and then your foglights, the relay is supose to kick in. You should hear a click. My forehead is getting sore from slamming it into the wall trying to fix this. I think it is going to the dealer.

Hope I helped.

 

I have a 98'.
My fogs didn't work when I got it, but since all the parts were there, I took the time to troubleshoot it.
The first thing I did was replace ALL of my fuses and relays in the car.
That includes the ones INSIDE and in the engine compartment "power-distribution" center. I replaced all of my fuses with the ones that light up when they pop. It cost me about 20$ and now I don't have to dig in that dam poorly placed foot panel.
Then, after reading many posts on multiple sites, I heard that the interior stock foglight switch was NOTORIOUS for burning out. It seems many people flipped it on and just left it on, running fogs and regulars continously... kinda making a hard life for that poor little switch. It cost about 30$ at the dealer, but I felt it was worth it. Also, if you have someone's employee number, you get a part discount. You also might check the aftermarket channels. Then, since I was STILL not working, I finally broke down and replaced the bulbs, just to make sure I wasn't overlooking the obvious.
Then... I opened the wiring harness from the fogs (at the point of the lamp) to check the colors of the wires. It seems ALL of the wiring diagrams I came across said different things. I had to take out the battery to follow the wire into the bottom of the "Power Distribution Center" (sounds cool eh?) which came out of the jeep remarkably easily.
Low And Behold... The HEavens Opened, and there was my Loose Wire! I tucked it back in, put it all back together, and rehooked my battery... resulting in the lights finally working.

Moral of the story....

20$ for fuses.
40$ for all new relays.
12$ for new bulbs.
40$ for a new factory toggle.

112$ total for factory fogs...

99$ (or more) for aftermarket with all wiring, switch, etc...

I guess it depends on how much you want the factory set up and switch..

Good-luck.

 

Yet another good by-product of doing it my way is...
Yes, you have all new fuses and relays-
One less thing to go out on ya.

Save the extras in a box in the barn, you might need em later.

 

Oh, also...
I NEVER found the fuseable link that some of the diagrams say exists in the circuit.