Join Date: Aug 2008
Location: Monroe, Louisiana
I'm far from a horn expert, but my understanding is it takes both the high and low tone horns to get the best (loudest?) sound. It may be possible to buy a complete relay assembly, but most are made to fit the vehicle they go on. If you do an internet search for "how to make a relay", there are many explanations with pictures. All you really need is some heavy gauge wire (think I used 10 or 12 gauge) a relay (available at any auto parts store), and terminal ends to attach to the wires going to the relay, battery, horns, etc. My electrical skills are extremely limited, but I was able to wire up a relay for the horns on the Rebel. A relay is needed for just about any after market horns as the OEM horn wire isn't heavy enough to provide the power needed to operate the horns. The OEM horn wire is used to "trigger" the relay.
IIRC, it's a good idea to include an inline fuse in the relay assembly so things aren't damaged.