I submitted this on another focus forum but I want to spread the word on what I found. If this has been discussed before - my bad.
Sorry that I am waking up an old thread but I felt the need to help out some others:
I had read most of the posts about the Fog Light Modification, however, none of them worked for me. I have a 2004 SVTf with EAP (and HIDS). Opposite to the typical Focus Fog Light Modification, I had to "CLOSE" the relay circuit, not keep it open. I have no idea on which connectors in the fuse box to jump but eventually I just took some #24 speaker wire (with the plastic cover on) and jammed it in between the relay contact back and those two small teats on the relay to keep the circuit closed on the relay. Any type of non-conductive material would probably have worked. I guess that I could have used some type of "conductive" material between the relay points to provide the same effect instead of jamming the points together but for the moment it works. You just need to keep the contacts closed.
FWIW, the fog lights are on even when your high beams are on. Some states frown on this. Caveat Emptor.
I hope this makes sense.
PS: Don't mistake the fuel pump relay (#7) for the fog light relay (#13) like I did. This is experience talking.
PPS: Oh, the ignition has to be full on not just half on for radio and etc.