For '94 and below, new contact pin is 84312-12040 and here is some info on the procedure:
https://tctmagazine.net/january-2015-volume-8-issue-1/80-series-horn-replacement
What year? If it is '94 or below, you probably just need to take off the steering wheel, replace the brass contact pin, and grease it up. If it is 95-97 it has a clockspring, which is expensive to replace.