I just picked up an 89 Chevy 3/4 Ton 4x4 and I've got a weird issue.. My horn only works when my headlights are on. I've looked and looked and cant find anything.. Is there a constant power that runs through the headlight switch and to the horn?
I've got a haynes manual but I cant find the horn in any of the schematics..
Any / all help is greatly appreciated...