horns wont sound unless engine running

A little unnerving when some painkiller'd out pasta eater is about to back his BMW into you in a parking lot , and only hear a relay click as you try to blow your horn. I have four note horns from a 73 Eldorado in my Caprice.

I appears that you have the wire hooked up to a "hot when iginition on" curcuit instead of an "always hot" wire. Connect the same wire to the "contacts" as you have to the coil of the relay.

That would be in the convenince center on the firewall? When installing my four notes I just spliced the harness into the factory thin gauge green horn wire. Would this have been something the NCSHP would have done, or were the 9c1 wired differently?

Brian

I do not know why the horns do not work when the engine is off. You stated that the relay clicked, but no horns. Somewhere you have either a bad ground, or a connection to a "hot with ignition on" circuit. You are going to be troubleshooting with a VOM. Start at the horn, and check for voltage, going back through the circuit until you find the issue.

Okay. Getting 12v at two orange wires on relay. Testing the terminal with the green wire , press horn my dvm says 9 volts.. testing main horn wire in engine bay im getting 7 volts.

Generally the orange wires are "hot with key on". The wires for my OCC are white. You may have a poor connection somewhere. You should get the same voltage at the green wire as you get at the input wire for relay. Make sure the relay does not have burned contacts.

SOLVED-

after venturing around with my 3$ harbor freight DMM , I figured my horn contacts were okay, so I wouldn't have to get my face torn off by an airbag.

then, I put down my joint and thought for a minute to myself, "this is the factory wiring and connectors from 1973.. let's check this harness." took some vice grips and plenty of PB blaster to get those little spade terminals apart.. a little battery terminal cleaner and a scratchy scratch with a pick and I've got my tugboat sound back!

the spade terminals had no visible green corrosion, just dirt and sand that had been sandblasted into them from the Eldorado's decades in AZ.

this produced some weird effects, sometimes even with engine running I'd have to sound the horn and my voltage/lights would dim dramatically.

so.... K.I.S.S.! keep it simple stupid!