Have you verified that you have power to the horns? It might be relatively easier to work backwards from the horns to the switch. Check the wiring and ground on the horns. If everything is OK, move towards the power source. The horns on my car didn't work at all when I bought it. Found a bad connector at the steering column. If you still feel it might be the push button, do a continuity check across the switch. This may save you from having to disasemble the switch.
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