I have the single wire S5 system that came on the verts, turbo and GXL luxury cars.
What really puzzles me is HOW does the system know how much assist to give, and how does it achieve the end result? As I said, there was only one little sensor hooked up, so what's going on to make it all happen?
@DJ: Well, I'm not sure if the S5 unit plugs into the S4 harness, and then I just got layed off, so i'm a bit short on cash right now. I'll take it for free though!