Doh! FOG lights I mean. LOL!
Maybe switch on the car and let it idle, then flick the silver switch and see if any lights pop up in the dash / cluster were your speedo and tachos are... Also hear out for any noises when the swtich is flicked...
Or take it hard around a corner then pull over, let it idle for a minute or 2, then flick the switch and take it hard around the same corner to see if it makes any difference...
My friend Tim GTR on SAU has a R33 GTR with a flick swtich and its for the 2WD/AWD switch and when you activate it, there is a a quick "Humming" or a very low tone "Beep" "Beep" noise.
But thats just his car.