Elpachio

Hi, I have a 95 Prelude with a horn that was fitted (non-factory) many years ago, so it has a double horn as opposed to the original. Anyway, it has worked fine for years but has recently stopped working.
Nothing else appears to have stopped working, just the horn. I located a fuse "marked" horn under the bonnet but the fuse looks absolutely fine, so swapped it with compressor, and it still didn't work. I have run a meter off the terminals at the horn and it is not receiving an electrical signal when I depress the horn on the steering wheel, so I can only assume that no signal is reaching it. As the fuse is okay, would you suggest that the relay be a problem? or something else?

I did spray some battery terminal protector on the wires around the horn a few weeks ago - would this have potentially shorted the circuit to the horn??

Thank you,
Steven