In fact I think U r asking about the fuse box, yes?
If yes, then U open the engine, U will find it on the right, its a black box, before U open, indicate the place of the horn fuse on the cover and remove it*
U will find it as an example, 10 A, U change it by another one from the box and try to make a voice by the horn, like this U r checking for the fuse performance.
if it works, then U have to change the fuse and thats it. if not, then U go and check @ the agent.
* To remove the fuse from its place,
U will find in the fuse box below U in the driving cabinet, a fuse removal, U can remove it and return it back using this tool,
Thank U and sorry for the long reply..
Cheers
المفضلات