how do you wire a horn?

i am trying to add an electric air horn to my tacoma and i cant get the relay wiring correct.

i want it to be seperate from my factory horn completely.
how do you to it

87 is the switch
30 is power with fuse
85 ground
86 horn
ground the horn neg side.

sound right?

relay terminals-
85
86
87
30

 

If you bought the air horn hit that has the small compressor and 3-2 plastic trumpets, the wiring is simple.

You may want to disconnect the battery before starting.

Here's the kit I used:

http://cgi.ebay.com/ebaymotors/Dual...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

1. Disconnect the factory horns from the wiring harness.

2. Mount the new horns and compressor where you want them. Point the horns downward towards the ground so they don't accumulate water inside.

3. Using a crimp on spade connector and the correct lenght of wire, crimp the spade connector to the wire, then insert the spade connector into the wiring harness where the factory horns connected, and connect the wire to the positive terminal on the compressor.

4. Run a ground wire from the compressor's negative terminal to a good grounding point under the hood.

That is all you should need to do.

I've been using this setup for almost a year and not blown any fuses.

 

You have a couple of those relay terminals mixed up.

30-battery with fuse inline
87-horn
85-ground
86-switch


You could also supply positive power to 85 instead of ground, and then use 86 to supply a switched ground to activate the relay. Most factory horns are wired with a switched ground to the relay.