What does this coaxial cable do?

[The Radium King]

have a look at what audi uses for this. just got a 2002 audi allroad and the immobiliser is in the same place, but in an oem waterproof case similar to a pelican case - might be useful to visit a wreckers and see if they have something.

[Qmulus]

Originally Posted by The Radium King

have a look at what audi uses for this. just got a 2002 audi allroad and the immobiliser is in the same place, but in an oem waterproof case similar to a pelican case - might be useful to visit a wreckers and see if they have something.

I am VERY familiar with Allroads... You must be a glutton for punishment! (I can relate, I have had a '00 A6 2.7T 6 speed sport for 16 years now...) The problem is those modules still get wet even with that box. More so with the transmission control unit that is on the passenger side floor and the ESP module as well. Make sure you clean out the drains on the plenum near the battery. They tend to fill up with debris, and in big rains water will come in around the cabin filter and down onto the floor. I don't get Audi's tendency to put electronics in places that tend to get wet. I have a big box of Bose amplifiers from newer Q7s and A6s that got wet. They are usually repairable, but it takes the whole MMI system down when it happens.

Just to be clear, the immobilizer is in the cluster on your Allroad. The module under the driver's floor is the Central Convenience module, that is similar to what the Boxster has, but has no immobilizer functionality and no where near the number of issues with them.