My horn didn't work when I bought mine either. I took the horns off and took short pieces of wires to hook the horns directly up to the battery, still nothing. So I went and bought new horns and installed them. Then, when I looked at the switch in the wheel,it was all corroded. After that was cleaned up, it worked like a charm. I would test the horns first and if they do not work, get new horns. Then go from there. Just start narrowing down possible problems.

1990 LWB 3.0 Auto Tan interior Mostly Stock 194k