My never ending battle with horns

Horns go bad or get out of adjustment. Are you sure they are grounded? Yeah, I know, I know, you MOUNTED them, here's a true story:

About 20 years ago, customer came in with landing lights (4537's, look 'em up) mounted in cans on his front bumper---bumper is bolted DIRECTLY TO THE FRAME of his old Ford pu. Lights don't work. I take a meter from battery NEG to the bumper and the BUMPER is not grounded!!! It's so rusty it's not grounding to the frame!!!

So pull at least one horn off, use a large wire and jumper the horn DIRECTLY across the battery until you are satisfied IT WORKS. Fiddle with the adjuster if necessary. Be careful when doing this you can get YES!! SHOCKED!! due to "inductive kick" from the horn

Then remount, be sure it's grounded.


You can also check the ground:

RECHECK power on the green with horn button down, I.E. power to horns.

Now put your probe DIRECTLY on the horn case, the other probe still on ground, see if you read any power