Thanks for the replies, guys. It was hanging from what looked like a custom harness w/ several cut wires (coming *from* the guidepoint). There was also an apparently associated button on the instrument panel which I couldn't figure out. It was rectangular w/ two square buttons, one w/ a phone-looking icon and the other a sort of grid, w/ a flashing (when power off) blue LED between them. That LED no longer flashes after disconnect.
I'll check w/ the guy I got it from. He hadn't had it long and didn't know about a few things so I don't expect an answer.
