...to help out with this one.

I'm about to get a 2000 S4, and I'm nothing short of delighted. After conceding to the fact that I'm going to have to rip out the factory Bose system and replace it with a custom-fabracated fascia, I've come across something else that could be considered a small point of note:

The factory Bose system has three leads coming from the head unit, as data lines to the dashboard. They display things like the radio station and the status of the CD changer and so on. They've got to be manipulated using a +/-5v current from the stock HU...is there anyone out there with the knowledge/know how to inform me a little more about this feature of the Audi's?

Thanks a lot!