HORN GOES OFF WHEN DRIVING OVER BUMPS IN THE ROAD
Loose connection. Check your connection at the actual horn and your steering wheel. It is most likely loose at the horn itself.
I had same problem in my porsche boxster. It was a washer in the steering wheel where the horn is. The washer was worn out. That's what caused the horn to go off when I braked really hard or go over speed bumps. I hope this info will help you. The dealer told me to replace the steering wheel for 2k. They didn't sell the washer separate.
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