Light Switch Diagram

[stuiedaman]

I bought an 03 expedition recently and added some fog lights to the bullbar. I am going to wire them into the stock switch for the fog lights but cannot figure out which wires are the fog light wires!! I don't have a volt meter and being Christmas no place is open to go buy one. Which wires are the +/- for the fog lights??

 

[Bedrck47]

you should get a copy of the Ford workshop manual on DVD