fog lights not working?

check with a volt meter that you are getting 12 volts at the fuse,next check you are getting 12 volts at the switch,next check you are getting 12 volts at the lamp fitting,lights are very basic things not hard to fault find or fix

mm
May 2013

Either both lamps have blown (unlikely) or you have made a wiring error (have you organised a good earth return path for the new lights?) or a switch or a relay is not working properly.

All this is conjecture - there may be some obscure other reason why your new lights are not working but you say precious little about what you have - the vehicle - weather the new lights are add-on new or replacement new.

Good luck...

Peccavi
May 2013