SpideyTT!!!

I've been looking over the Bentley wiring diagrams in preparation for doing a mod to enable the fog lights with just the parking lights on (normally, they are on only with the xenon low-beams).

I'm pretty clear on how to do the mod, but I am confused about the Fog Light Relay (J5). The coil of this relay is connected to +12v via Fuse S3 and the Headlight switch (on with parking or main lights). But interestingly (according to the diagrams), it is grounded via the high beam lamps! The effect is that if the high beams are off, current flows in series through J5 and the high beam lamps to ground. If the high beams are on, +12v is applied to both sides of J5's coil, and thus it is deactivated.

Does it really work this way, or is it an error in the diagrams? If it really is like this, why?

morrisdl

The other lights shut off automatically when the ignition is shut off. I would love to have all the exterior lights shutoff automatically when I turn the car is off. Anybody try this mod?

Would having the xenon's turn on at the same time as the car starts up be bad for the lights?

ND4SPD

Probably since you cannot run hibeams in most cars when the fogs are on and vice versa.

Stinky J. Sock

At first I thought it was a TT without the performance package, thus no xenons. But as it got closer, I saw that it only had the fogs on. Since the fogs are in the same housing as the headlights, I thought it looked kinda stupid. Rather just have the glow of the xenons. If the fogs were in a separate housing (like on a Beetle), then maybe it would look ok. Again, just my humble opinion.

jackTTar

current draw from the battery so to help start the engine.

msauve

This definitely works with the Euro headlight switch, and should work with the US switch.

Get a wire with the correct contacts from the dealer, p/n 000 979 133. It's about a foot long, with contacts at both ends. Cut it in half

If you would like to be able to run the fogs without the headlights (by pulling the switch out when it's in the parking light position), use the half of the wire w/contacts and insert it into position 5 of the connector. Then connect that wire to the wire coming from position 4. Position 4 provides power for the fogs when the switch is on headlights, position 5 provides power for the fogs when the switch is in the parking light position.

The relay turns the fogs (and rear fog, if fitted) off when the high beams are turned on. It does not turn them off when simply "flashing" the highs.<ul><li><a href="https://forums.audiworld.com/tt/msgs/724807.phtml">...rear fog wiring, fogs w/o headlights, more...</a></li></ul>

JustJeff

See my post on this modification.
My mod does what you want.
Gives you the ability to turn the fog lights on with the parking lights.

You DO NOT mess with this J5 relay, but you do need another one, and a remote switch to make this work.<ul><li><a href="http://home.attbi.com/~jbipes/ttr/fogs.html">Fog Light Mod</a></li></ul>

RobbyTT

Hey! Was it me?? (I run fogs as DRL)

SpideyTT!!!

1) I don't care how it looks.

2) In real fog, using fog lights alone is much better than fogs + xenons. This is because the xenons are just reflected back at the driver by the fog, while the yellowish fogs penetrate better.

3) Given that I drive a tiny little roadster on NYC metro area roads with NYC metro lunatics, I often keep my lights on even in daytime to improve visibility (essentially DRL's).

4) What I care about here is safety, and the ability to flexibly choose the most effective lighting for the driving conditions.

SpideyTT!!!

Interesting thing about this way is that the fogs will be enabled regardless of dimmer switch position if both high-beam lamps are burned out...