Good afternoon. Im having an issue with the fog lights on my 98 a4 2.8 quattro. There are two buttons on the dash which im not sure why? When I push the one with the squiggly lines pointing down both buttons light up and the one with the lines pointing straight out lights up by itself when pushed. So. Absolutely nothing lights up on the outside of the car when pushed. Previous owner put aftermarket fog lights in bumper which were ran off a remote which he lost. Check fuses in the dash and all look good. Car has no manual so im winging it! Thanks!

 

The button that points down is the front fogs in the bumper. In a stock B5, you can turn those on by themselves. The ones that point straight out is the rear fog light. You have to turn on the fronts before you can turn on the rear, I have no idea why. The rear fog is in the driver's side tail light. It's just a very bright red light.

 

This is not true (at least in my case).

The button to the left is for the front fog lights and should always work (as long as your headlights are on).

The fog light button on the right is indeed for the rear fog lights, but that should not work/come on unless you've done the "rear fog mod" (US models didn't come with rear fogs).

If you do have the rear fog mod, then you can push the rear fog button by itself and it will turn on all 4 of the fog lights and light up both buttons (There are 2 fog lights in the back - not one - on mine at least).

Try turning on both buttons and see if the rear fogs come on (They will/would be at the top of the tail lights).

As for the fronts: find the wattage of the lights. If it's the same wattage as factory, just tap them back into the factory wiring (which should be lying around right around there somewhere).

G/L

 

Always a chance something's wrong with mine. But it's hard to believe that's just a short in the wiring. On my 99.5 the rear fog is dependent on the fronts. Might be something that changed with the year.

 

Rear fog light? Strange. Any way thanks for answering. The after market fog lights were cut into the plastic by him. I dont see where stock ones would have been. It wouldn't be the third bulb in the headlight would it? I have a high beam low beam and some other bulb toward the bottom of the headlight assembly.

 

Sumbitch. Yea pre-1999.5 the front fogs are the third bulb in the headlight. But you still should have a rear fog in the left tail light. My dear departed 96 A4 had one.

 

I can't speak for facelift cars, but on prefacelift cars (like OPs 98) the front fog lights are turned on automatically by the rear fog light button, even if the front fog light button is not depressed. In the switch wiring there is a jumper between the rear fog power and the front, that circuit doesn't work in reverse though.

All US B5s came with one left rear fog light. It is only supposed to be used in very low visibility conditions to allow cars behind you to keep track of your position. The US required it to be one light to prevent confusing it with brake lights.

OP, the stock prefacelift fog lights are located in the headlight. It's possible the previous owner disabled them. You can check to see if the headlight plugs still have a green/white wire going into them or if it has been cut. Wouldn't hurt to make sure the bulbs aren't burned out.

 

This is why I don't understand people who do the rear fog mod, you're basically running around with both brake lights on constantly which is just stupid. It's a safety thing that should only be used when the weather bad enough that you can't see the car in front of you, and yet I see so many cars driving around with the rear fog on in perfect weather.

 

Mine is 2001.5 (Face lifted) and yes: the rear button turns both on.


I am one of those people - who did the (dual) rear fog mod - and I use them 24/7 (day & night driving).

You think it's stupid? That's your opinion. You think it's a "safety thing"? Have you seen the LED tail lights on almost every new car out now? Their tail light are brighter than my rear for mod and brake lights all on at the same time.....and I won't even get into how bright their LED brake lamps are. So, yeah: it's a safety thing for me too. I'd rather you see me than not. My rear lamps and rear fog mod aren't half as bright as a new car's factory led tail lights.

You do what makes you happy. I'll do what makes me happy. What I like doesn't make me stupid just because you don't agree with it. It's just something you don't agree with.

 

This isn't a matter of opinion, you're literally driving around with 2 of your 3 brake lights on. LED tails are bright, but you can at least tell when they're braking because of how the lights are arranged. If your 3rd brake light were to go out, everybody behind you wouldn't know when you're braking. Don't matter how visible your car is when the people behind you can't tell if you're braking or not. I've never had any issues spotting tail lights in everything but the worse possible fog/rain/blizzard (aka conditions that the rear fog was designed for), so don't try to tell me that running 2 brake lights always on will make it safer in the middle of the day. Also love the logic "damn these bright LED tail lights blinding me, better brighten up my tail lights too."

There's a very good reason the rear fog turns on only one light, you just threw that out the windows because LED tail lights are really bright and you want in on some of that action.