Ok, I am still trying to find an answer to this…
I am installing a second horn that will have a separate switch. I bought the horn used. It currently has ONE wire coming out of it that is connected to a switch. The switch then has a second wire coming from it (that includes an inline fuse). (The horn will be bolted to the frame grounding it.)
I was told I should use a relay. My relay has four prongs.
1 for ground 85
1 to power supply (fuse box via add a fuse) 30
1 to horn 87
1 to switch. 86
The problem is:
If I connect the horn to a relay prong and the switch to a relay prong, then I only have one wire coming from the switch. The switch has two terminals. Do I not need to use both terminals?? From my understanding a current needs to flow in a loop. But every time I see this question online the answer is always to just connect the switch to the relay. How can that possibly work? What does the other terminal in the switch need to be connected to?