Steve H wrote on 09/04/15 at 21:34:29:The relay will be a small black box. Probably $10 or less at the auto parts house. You'll need wire heavy enough to handle the load for the longest time you think you'll be blowing the horn and the connectors for the relay, horn, etc.
Check the diagram. Apologies for the horrible drawing capabilities but it should get the point across. Always fuse any new circuit you add.
In the second circuit, the horn button energizes the coil in thye relay causing it to close and deliver power to your horn. This will protect your horn button from heavy loads that could kill either the button or the original wiring. The new circuit will carry power straight from the battery through the realy and to your horn giving you full power and volume from your horn.
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This sound right, i suck at wiring and prefer not to burn out my harness.
1. Remove the wires from the horn
2. Attach these wires to the relay, one side to the relay the other side goes to the switch
3. Add 1 heavier wire from the battery to a inline fuse
4. From the inline fuse to the relay
5. Out the relay to the horn
6. Then from the horn to any ground
Pressing the horn button, using the stock wiring, closes the relay protecting the switch from burning out. Then the heavier new wire would carry the needed power to the upgraded horn.
I already have some 16 awg wire, would only really need the proper relay and a place to hide it.