The Stovebolt Site Forums The Shop Area The Electrical Bay The Horn, is it repairable?

So, my truck has an original horn. It has worked before but doesn't now.
I know how it i supposed to work. The horn is always hot, and you ground it by pressing the horn button on the steering wheel.

When i press the horn button it just gives a little "cough".
So i tried to just connect an other 12V battery straight to the horn (just plus and minus, no relay) but still it just says a little "Gmeeh". Hard to describe, but it doesn't sound like the horn should. So i wonder, how should i repair the horn? Can i take it apart? clean it up? I've tried to find something useful by searching the forums but i just wind up getting information about how its wired.

thanks a lot in advance!