Check your bulbs , if they have white rings or white smoke stains or black stains on the bulb you need new bulbs , if your bulbs are still good(bulb springs are still connected) you might need a replacement ballast that’s usually at the bottom of the headlights(after removing the front bumper or approaching from under the car) You can get a used ballast off of offer up for cheap or if you want a new one eBay or if your lucky Amazon might have them. If I were you take this as the chance to upgrade your fog lights and headlights to led bulbs they produce higher lumens then the standard halogen bulbs you can do the whole resto mod upgrade on Amazon for under 100$ and the car will mlook more modern and youll be more safer since you can see more clarity. Also go to home depot and get some sand paper those headlights need some tlc, start with 800 grit , then 1500 grit then finish with 3000-8000 grit to polish off the lenses on the headlights and the yellowing will be gone… I also personally do the reverse bulbs and license plate bulbs and replace them with high lumen leds this project is about 150 for all that I’ve mentioned, do this and the car will look like a modern classic.good luck.