Why big red wire making relay click?

[Formerly Steve Wilkinson]

Having finally traced the dead-short-to-ground in my '83 SC to the big (6mm) red wire that fastens directly to the positive battery terminal (along with a pair of 2.5mm red wires, but they're fine), when I touch that red wire to the battery post, with everything disconnected from the battery but the ground strap, it makes what sounds like a relay click. Click, click, click every time I make and break the connection. Anybody have any idea which relay it is? Sounds like it's coming from somewhere either under or forward of the instrument panel. And, of course, I'm assuming that the relay should not be closing, and that it is the source of my battery drain, right?

Stephan