Installing a second Horn
This is for a Bosch relay.
A power wire goes to one side of the switch. The other wire of the switch goes to relay terminal 85. terminal 86 gets a wire to ground. 30 gets fused battery power. 87 goes to horn.
When you turn the switch on, a small current flows through the switch to the relay, completes the relay ckt, closes the contacts, and allows a larger current to flow from pin 30 to your load.
What we've got here is... failure to communicate. Some men you just can't reach. So you get what we had here last week, which is the way he wants it... well, he gets it.