My 99 disco. came with factory fogs installed on the brush guard (also factory) But cannot get them to turn on! I have followed the wires from lights to fuse box behind the main fuse box under hood. power is getting there, and to dash swicht. But there is not power to the lights! any thoughts?

 

Disco 1 or 2 ?

if its the factory kit in a Disco 2, which is quite unreliable, then they will only work with "full beam" on

 

Those are not fog lights, theya re off road driving lights and it is illegal to use them on public roads with other cars.
Like Panzer said, the high beams need to be on for them to work.