Hi there! I have an issue with my fog lamps. They will not turn off unless I pull the fuse. If I put a fuse back in, they turn on. For a while, I was running LED fog lamps. They started not working. So after a while I tried standard halogen bulbs, just for grins and giggles, I got out of a Monte in the junkyard. Amazingly they turned on! However... sometimes they would blink on and off for a bit before staying solid. I had also swapped in a different headlamp switch.

NOW... they do not turn on at all. The fuses do not blow. Could it be the bulbs? Could it be the swapped in headlamp switch unit? Could it be the bulbs themselves? Any help would be appreciated!!!

 

I think the best path here is the same as your other thread- break out the wiring diagram and a multimeter.

If they're not working at all, check for power and ground at the harness - if you're missing one, then continue checking upstream until you find where it gets lost.

 

Check the fog light relay and wiring first. Even if the fuses are fine, a faulty relay or poor contacts in the swapped headlamp switch can cause issues. Also, make sure the fog lamps have a good ground, as a bad ground can cause blinking or failure to turn on.