The horn push in the centre of the steering wheel needs a firm push; the incident is usually past by the time you have applied sufficient pressure!
The horn is located in the wheelarch (behind the liner) in front of the left wheel.
The horn contact in the centre of the steering wheel:
- feeds through the COM2000 unit under the steering wheel (has been known to cause problems - re-seat all the plugs)
- and into the BSI which controls an IC in the engine compartment fusebox
- which in turn operates a relay in the fusebox (supplied by F13)
- which operates the horn (mostly the problem)