Reading wiring diagram

[kervinridgley at earthlink.net (Kervin)]

I'm still having trouble getting my horn to work.  I have a 86 8v Scirocco.
My horn relay is not opening when it is in the car.  My question has to do
with the labeling of the Terminal connections at the fuse/relay panel.  I
need to find connections A25, L1, L2, L3, L4, B25, C13, and C15.  Well, I
did find A25 only because there are 2 BK/Y wires at that spot.  I don't have
a oil temp gauge, so I checked for current at that spade.  Anyway, some help
would be great.