Dave sez, "You can also try supplying your own 12V and ground to the horns individually." Do this.

Temporarily run a wire directly from battery + to the horn. It's the only way to know whether or not the horn is the problem. If still weak sounding run a temporary ground wire and try it again.

If you really want a horn that sounds with, "authority," get one with a strong note (think American car horn) that grounds through the mounting and use a relay. The horn button grounds the relay which closes to provide power to the horn. Get power from the hotspot on the left side of the engine compartment.


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'79 242, '84 DL 2 door, '80 DL 2 door, '89 DL Wagon, '15 XC70 T6 AWD