Horn issues

It is 46 degrees outside and very foggy and moist. I just installed a set of “GG” train horns in the bed of my truck yesterday. This morning I woke up and got on the main road and the horns would not sound. I kept messing with it, pulled over, checked the wiring and so on (I could not hear the valve click open). Every now and then I can get it to make a shrill toot. I am running them at 200 psi, what should I check first? Diaphagms are not damaged, I am guessing that I should wire it into a toggle switch instead of the stock horn switch or it is a bad valve on a brand new horn? Yesterday I used the hell out of it with no problems.

Could it be a ground issue?

do you have a multimeter? see if you can check that out on the valve if you can’t even hear it clicking open

check the ground for your valve it might have came loose, thats what happened to mine, i didnt have it tight enough and it stoped it from working. It was a easy fix.