1982 Cadillac Other

Electrical problem
1982 Other Cadillac Models V8 Two Wheel Drive Automatic +100k miles

My horn in my cadillac hearse is not working. When I press the button I can hear the relay click. I put a test light on each horn and they are getting power. I took the horns from a parts car, hooked them to another vehicle and they work. I put them in my hearse and nothing. I removed the relay. Ran a wire straight from the battery to one side of the relay, another wire from the other side of the relay to the horn. I used the test light to ground it to the car. The test light came on but no sound. What am I missing? Shouldn't the horn blow when there is power applied?
Thank you for your help
July 18, 2008.

We got it, it was an extremely bad ground connection.

Jul 20, 2008.