Where can I find Citroen Berlingo 1.9D 2003 fuse layout diagram?

Where can I find an electrical diagram / fuse layout diagram for my 2003 Citroen Berlingo 1.9D van?
I have bought the Haynes manual for the correct year, but the drivers side fuse box is completely different to the book.
Not as many fuses, and all fuse numbers (F1, F2 etc) have different ratings to the book!
So which one does supply my horn? Citroen website provides zero maintenance help and is completely useless.