rovision

Taking the right tail light out, the usual burnt light issue, I've "discovered" this empty socket. It's in the lower row, to the left, next to the trunk. Large socket, similar to the usual brake/running lights. Any idea what's this for?

lyleswk

Believe that is normal. The second position on your fog lights (2nd detent after light switch is in on postion) turns on the rear fog which is only in your left tailight. Hence the empty location in the right. Take a look at your manual for info as well.

AudiCO

Yeah, I believe the dual rear fog light applies to continents other than North America but is deactivated here, even if you insert a bulb (might work in Canada). Probably a good thing as I can't stand driving behind people in Audis with their rear fog light on if the visibility is clear, simply because they don't know what the switch does. Two would be worse.

rovision

I'm not near the car now, but AIR, isn't the fog light in the top left corner, same with the brake/running light?
About the single fog light, I've been in situations where visibility in fog was under 10-15ft and definitely would've appreciate any additional rear lights on the vehicles ahead of me.

After checking, yes, the fog light would be in the same position on the left side. So, the empty socket is an empty fog light socket.

AudiCO

I have no problem with rear fog lights when visibility is low, such as when there is actually fog, or more commonly here, snow. But the majority of times I see them in action is at night in the city and people have no idea that their rear fog light is on. I find it annoying almost to the same extent as people driving up behind you with their high beams on.

Only one side works so that it is easier to differentiate between fog lights and brake lights.

lyleswk

I am with you on the rear fog; don't like it on unless it is low vis which where I live is about 2 days a year. What is your opinion on the fronts? I like running with them on all the time becuase of the additional lighting (probably my old eyes) and don't think they cause issues as long as they are aimed correctly.

AudiCO

I run the front fogs most of the time, not always. I replaced the factory bulbs with Hoen xenon match bulbs simply for their aesthetic value. I don't think the additional light improves my visibility much or harms others' since they're lower than and not as bright as the HIDs.