I had the same problem with my horns. No noise... but tested both by hooking up directly to the battery terminals as recommended by another. Cleaned up connections, ground and fuse and got the high horn to work. Some suggest a spray of WD-40 into the opening - I did that as well.

The low horn (passenger side horn) was a different story - nothing seemed to work. I opened it up (took some doing as the bolts were nearly frozen on) - inside is something that looks like breaker points - I used sandpaper to clean up the points, put it back together and it worked! There is also a phillips screw at the back that tunes the horn - I loosened it a bit I think and that helped clear the throat as well.

Both high/low horns sounding together - sounds really sweet.

waggin.

65 120 wagon, 85 240 turbo wagon