2003 Navigator Horn Inop

[rowekmr]

Just bought this truck and had some repairs done and discovered the horn is inop. I guess I should have checked its operation earlier but found out when someone cut me off in traffic and I try to blow the horn...lol.

Where is a good place to start trouble shooting or diagnosing? A little background I bought it with most power options and air suspension inop. Had shop diagnose and replace the central junction box (fuse panel under dash) for the power options then the air compressor relay and door switch for the air suspension. Is it probably just the switch/contact in the steering when or something more complex?

Thanks