@Martin an gof
Funny...I'm going through this exact thing right now with the wife's Jeep Wrangler.
Took it to the dealer (I know...read on) several months back, for [Takata] airbag replacement recall, and just a few weeks ago, discovered that the fog lights no longer turn on.
I have been all through the wiring and such, nothing's damaged, and there's even voltage *at* the lights, but not enough current to turn them on. Seems they're controlled by the computer, and there's an option bit in the memory which is set if you have paid for fog lights, and cleared if you have not. So, even if you add the control stalk with the fog light switch, and add the wiring, the damn things won't work unless the computer has that bit set.
So...they *used* to work, car came with them, but ever since the dealer changed the airbag, they...don't. I'm replacing the control stalk on the off chance the switch is bad ($90) but my money's on the dealer reprogramming with the wrong image or something when they changed the airbags.
If I have to go back to the dealer, I will be going back with a complaint. Unfortunately, I have not a leg to stand on, and no way to prove they did this, but if they magically make them work, and try to charge me, there will be some discussion. I will be asking them exactly what they did to make the lights work again, and if it involves the "fog light disable" bit, I'm going to raise a stink.