You issue sounds like the horn switch under the pad is defective. This is pretty common for the contacts on the switch to fail. Sometimes they can be cleaned but you have to remove it to do that so it just better to replace it.
You proved out that the horn works not only by the panic button (this is from the module to the horn circuity) but also that it works when pressing one side of the pad down. This indicates that everything except the switch is working.
Let me know if you have another issues.
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Friday, April 26th, 2019 AT 1:16 PM