Horn wiring question

[AngryPirate]

So, I've replace the steering wheel guts for the horn (correctly I assume) and then I'm trying to test the green wire coming out of the other side.

I was assuming that pressing the horn button creates a ground, so with my tester ground-side attached to the green wire and the + side touching some power. So I would expect when I press the horn button the tester light should light up. It doesn't.

Next question, does anyone have a picture of how the horn relay is wired? I looked at the wiring diagrams and I don't think I can glean from those which wire goes where on the prongs of the relay.

So, is my assumption on the horn button being the grounding part of the circuit correct?

Just a note, I'm no longer using a voltage regulator external module either; just a alternator with an internal regulator.

Thanks for any help!

- Scott