This is just an update to this thread.
When I recently discovered my horn had quit working i went through all the steps to test and make sure it was actually getting power. Once I determined that it was the horn that was faulty I removed it and bench tested again with an old battery and some alligator clips on the terminals and it still didn't work.
I went thru the process of shooting WD-40 into the horn opening and sloshing it around and still nothing.
A couple weeks had passed and the horn still sitting on the bench I decided to test it again by putting the power to it and still nothing.
The difference this time was I figured i had nothing to loose and tapped the side and back beside mounting bolt with a small piece of brass rod and it started to operate intermitenly, but not steady or very loud tho.
At that point still thinking i would be throwing in the garbage I decided to mess around with the adjustment screw that is factory covered with silicon and ended up removing it and shooting a little bit of WD-40 in the hole.
This is where things get interesting and remember that i still have the leads connected so the horn is getting power as i'm putting the ajdustment screw back in the horn begins to function but this time with a steady tone.
Now I simply adjust the screw til the horn seemed the loudest and put a new bloob of silicon on the head of the screw and reinstall the horn back on the car, push the horn pad and it seems to function as it should.
Just thought I'd pass on the info for anyone that wants to save a few bucks and feels like a little challange.
261000kms and counting,,,,Wondering when the SPI will blow up!