There are a lot of things you need to look for when working on the
horn circuit. So lets indentify the parts that make up the circuit.
Horn Button
This button is from a T1 A (screw terminal, minus the screw)
Back Side of the Horn Button
Ever wonder what inside the horn button. It is important because it
is part of the grounding circuit.
The base of the horn button inside has a "spring tensioned" lever,
that when the horn button is pushed it closes the circuit and completes
the "ground" at the horn button assembly.
Here is how it all works, just push the "activate" button below.
Next we have the "horn hub" which sits in the steering wheel hub.
This group consist of the "hub", 3 rubber grommets, 3 ceramic
sleeves, 3 cheese head bolts and washers. Completely assembled it
should look like this.
This photo shows the hub" assembly installed inside the steering wheel
hub. This assembly is a T1A (Note the screw terminal securing the "+"
purple/black wire). The loose brown wire is secured to the back of
the horn button.
If you following this advise from a very wise "old-timer",
your troubleshooting skills will improve at least 50%.
"Always test the device first, then test the circuitry." - Joe
Leoni -356Electric.com