I just put in a new horn today and used the factory wiring. I had the steering wheel off so I but the horn contact and wheel back on. Reconnected the battery ground and the horn blows. Idk what it is. It’s like the contact is always compressed but I double checked it and it’s installed correctly. Any ideas?
On my 70 I had the contact plate on upside down in the steering wheel, created the same issue. Not sure what year you have. Hope this helps.
Check that horn contact plate like everyone says, odds are something did not go back together corrrectly, bent or broken peices. It doesnt take much to make it act up