Classic/Antique Car Repair: horn switch wont make horns sound, Horns wont blow

Question
The horns on my 1968 Pontiac Catalina do not sound when I press the horn button on the steering column, but they do sound if I touch a 12V lead to their ungrounded terminal.

There does not seem to be any continuity between the small wire connector under the horn button and any of the wires going to the horn relay. I'd like to add a wire from that small wire connector under the horn button to one of the horn relay terminals, but I cannot see where the wire from that small connector exits the steering column.

Can you tell me where does the wire from the small lead under the horn button exit the steering column?

Answer
Before you go to a lot of trouble replacing the switch wire from the relay "S" terminal to the horn button in the steering column, check your horn relay to make sure it is good and has power.  You do this by grounding the "S" terminal on the relay with a temporary wire.  To identify the "S" terminal, if you can't make out the letters on the relay, use this method.  One of the wires on the relay goes to 12 volts - it is hot all the time - check with your meter or test light to see which terminal that is - that one is the "B" terminal.  Next, one of the wires on the relay goes to the horns - that should be obvious by noting where the wire goes; that one is the "H" terminal.  The last one is the "S" terminal, and if you ground that, it is the same as far as the relay knows as someone pushing on the horn button - the horns should sound. If they sound when you ground the "S terminal, then your problem is indeed the switch in the steering wheel or the wire you suspected all along.   The switch can be very tricky to fix - especially if it has the "rim blow" steering wheel.  If you have that problem, you may have to send the wheel out for repair, or provide some other way to ground the wire to the horn switch.

As for where the wire is routed, it goes down the inside of the steering column jacket, and exits as one of the pins on the multi-wire connector that also operates the turn signals.  The horn wire is usually black in color (but not always!)

Dick