There are a lot of things you need to look for when working on the
horn circuit. So let's indentify the parts that make up the circuit.
This button is from a T1 A (screw terminal, minus the screw)
Back Side of the Horn Button
Ever wonder what is 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
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