The horn was working fine on my '46 6400 PW (2-ton) but then just quit. Horn is fine but the wire going up the steering column is open (will not ground at all) no matter what one does with the button. I pulled the button and steering wheel expecting to find some sort of contact but there is nothing -- the button pushes on three fingers which in turn go through the hub of the wheel and push a collar on the underside of the wheel down against the outer steering column. I cleaned up all internal surfaces to shiny metal including the two springs just incase but no change. I also don't meter any voltage on any part of the steering column at the top. There's also no room whatsoever for a wire to make it past the top bearing so I'm confident that it's not just missing or pulled out.

How is this supposed to function? I'm assuming the wire entering the bottom of the steering column is connected to part of the steering column and the horn button serves to short the outer to .... something?

Thanks in advance

Pete P.
Harborcreek, Penna.