Horn Blaring

When I bought the car the horns were not connected. I plugged the 1st horn in , and it immediately started blaring. Does this mean the rim blow switch is bad, or possibly dirty.
1970 Cougar XR7

That would be the first thing I would check.

The pad should come off easily and the connections from the switch to the slip rings on the steering wheel will be easily accessible. Unplug either one and the horn should stop.