Removal
Raise and support the vehicle in front on the left.
Remove the wire (1) from the signal (2).
Unscrew the bolts and remove the horn from the mount (3).
Examination
Connect the horn to the battery using additional wires. In this case, the contact for the orange/yellow wire must be connected to the positive contact of the battery, and the other to the negative contact of the battery. The horn should sound.
Installation
Install the horn, remembering to put a toothed washer under the mounting bolt. Put on the wires.
Lower the car.