Bill brings up a good point, have you run a known good ground wire to the horns with the wiring harness to the other horn terminal and tested it that way?
S2? Go under the car with your voltmeter, and make sure that when someone presses the horn button, there’s power. It’s not uncommon for Lucas relay contacts to go non-conductive. If this is the case, you can replace the relay or open the case and dress the contacts. If there is power, then it’s just a matter of improving the gorunding.
The horn circuit can be confusing…the relay winding is powered off of fuse 6 and the relay contacts are powered off fuse 3. So it’s never just one thing.
I think Don has an S1 OTS (1966)
Hi Bob, Mike, Bill… thanks for your comments… My horns do not have separate ground wires, I assume (there goes that word) that they are grounded by the mounting bolt… when I tried to just jumper the new horns to the + - of the battery, I just used some small wires, and maybe they won’t carry the currant needed to work the horns… will get some heavier wires to check next… about the only thing I really know about electricity, is that when the smoke escapes, nothing works.,
Don, my old horns and the new ones to replace them had two terminals for connection to + and - Granted they were on a Series 2, but I would test again on your battery and make sure you use a jumper to ground the horn to a known good ground point before using another jumper to the + side of the battery.
Are the new horns for a Jag?
I thought the smell of the smoke was a new cologne called “Essence of Lucas”