Section 58 (Steering Column Switches): Testing: Horn
WARNING: This page is about a different car, the 1994 Mercury Tracer and 1994 Ford Escort. However, it is still accessible from the selected car via links, so may be relevant.
Unplug horn switch connector(s). Continuity should not exist between horn switch wires with horn button(s) released. Press horn button(s). Continuity should exist.