Fog lights not working?

Okay so I did the fogs on with the parking lights, everything was working fine for a while. Then last winter the fogs stopped working. Then in the spring they started working agan. Now they aren't working again. Pull the fogs out and switched them with a newer pair I had, still nothing checked the fuse, checked the relay, checked wiring everything seems to be intacted. Checked to see if I had 12 volts at the harness where the fogs plug into the wire harness and there didn't seem to be 12 volts there. Any suggestion or help would be greatly appreciated.

Thanks,
Chris
 
Check for corrosion in the wires. I had a similar problem a few years ago. I rewired them and haven't had any issues since.
 
Check for corrosion in the wires. I had a similar problem a few years ago. I rewired them and haven't had any issues since.

My wired look good. I am thinking I might have a bad switch. When I push the button in to turn the fog lights on, I don't hear the relay engage. But when I disconnect the wire and touch the wires together at the relay I can hear it clicking.
 
I would think that's what it is. I know since I did the mod my light on the switch isn't working. Hopefully mine doesn't quit on me. That mod comes in handy with really thick fog on pitch black roads.
 
I would think that's what it is. I know since I did the mod my light on the switch isn't working. Hopefully mine doesn't quit on me. That mod comes in handy with really thick fog on pitch black roads.

Yeah man, I'm gonna replace the switch and see if that doesn't fix the problem. It is a handy little mod.
 
Well I am still having an issue with these damn fog lights. Installed a different switch, still no fog lights and the light on the switch doesn't light up anymore. Any ideas? Thanks.
 
Well I am still having an issue with these damn fog lights. Installed a different switch, still no fog lights and the light on the switch doesn't light up anymore. Any ideas? Thanks.

Are your bright lights "on?" Sounds silly I know but happened to me. Was wondering why all of a sudden my fogs wernt working . I had, as well, wired them to the parking lights so not having the headlights on didn't illuminate the high beam indicator on the dash (or turn the high beams on). So you could have them switched on without having any indication.
 
No, my brights aren't on, but my fog light switch isn't even illuminated anymore. So I don't think I am getting power to the switch. I am clueless to what happened
 
Sounds like you are pretty competent when it comes to wiring, so the only thing I can suggest would be start at the lights and work your way back. I haven't been into mine enough to suggest any specifics and I don't have a diagram on me either. When you checked for 12v at the plug did you use an independent good ground? If you probed both terminals at the plug you could be getting 12v and not know it if you had a bad ground. If no power there I assume the relay is next in line? Check for power coming into the relay again with an independent good ground source. If you have power there then ground out the relay and check if you have lights. If still no lights try bypassing the relay then you should have fogs and the relay is bad. If you don't have power coming into the relay to begin with then move on to the switch. If I recall this is where it gets hard without a diagram I want to say there are more than a few wires there but the practice is the same. Check for power in and out. Try grounding out the switch and/or bypassing to determine weather or not the switch is bad. Keep working your way back all the way to the fuse. Something could be messed up in the headlight switch too.

If you think the cold temps has an effect then you could have a loose connection somewhere so that when the wire shrinks in the cold it actually unplugs itself.

Good luck hope this helps.
Oh it might also help to use a volt meter instead of just a test light to confirm you have the full 12v and are not getting a voltage drop.
 
Matt, once this weather breaks I am going to go out there and trouble shoot those fog lights untill they are working again. I'm not sure if I was using a good enough ground but I will make sure the next time. I have a pretty nice multimeter. Thanks again for help... Happy holidays.
 
right now I am having the problem of one of the lights not working I just changed out the bulb plugged it in a get nothing not sure when I got in my crash some thing may have been cut? but everything else work that on that wire.. So I am not sure whats up...
 


Broke my foglight bolt taking it out, so now im down a light, im not even gonna touch the other one in case it breaks too. If it does im screwed because my CAI filter is right behind the foglight
 
Okay, so I figured out my fog light issue.. I checked for 12 volts at the fogs, and nothing. So I took on lead touched it to the fog harness, and one to the frame, then I got 12 volts. So then I checked the connections where the 2 harnesses clip together. And the middle pin was all bunt up and wasn't making a good connection. So I cleaned it up a bit and connected the 2 clips. It made a solid connection because my fog lights are now working, and I plan on changing the clips with new ones so this problem does not keep happening. Does anyone have a clue on what would cause the harness to burn up like that? Thanks everyone for the help.
 
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I wanna know about this too. My drivers side low beam has that issue too, and it's really annoying. Maybe it's from current surges or something?
 
I too have this issue with my fog lamps.
1st- changed out bulbs( old ones looked fine,but swapped anyways)
No surprise went to test them before reinstalling. No light!
2nd -tested for 12v at connectors.(w/know good ground) I got a reading of 0.02v on both lamp connections.
3rd- checked relays..all good.
4th- disconnected switch and tested for power at connector. 4 pins. One was ground. Two had consant 12v.( checked with meter and test light.) and the last one was power to ground( used test light hooked to ground and got 12v at that pin. Still confused. Bad switch or a voltage drop? Too late to continue work in the am. I will take pictures and post a wire diagram and switch diagram.
 
Okay I got it fixed. The fuse box under the hoo has 2 fog lamp 15amp fuses. I missed one of them last night. I have a picture of the diagram for the wiring. But i don't know how to post pictures here. Any one who can tell me how i will post it. Thanks
 
I have a similar issue with my fog lights. the switch doesn't illuminate when i press it, the fuses are both fine. the bulbs are fine. no voltage at the bulbs. where is the exact location of the relay? If that doesn't work I'm just going to wire a whole new circuit to it and switch because screw electrical issues. lmao.
 
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