Someone please help me with my fog lights

My Ebay fog light kit has been installed for over a year, now they do not work. Bulbs are good, I have looked over the wiring countless times, and rewired multiple connections, everything appears to be good. The cheap switch lights up and the relay "clicks". Here is the messed up part, I took the relay out to test it, it tested good. I put the relay back in, the fog lights worked for a few hours and quit again! I took the relay back out and left it out for a few days to think. I put the relay back in, the lights still didn't work. I checked things over, banged my head against the wall a bit. I then decided to give up for the night, as I was driving down the road they turned on! Fog lights worked until my destination, when I arrived at my destination I checked over the wiring to try and make them not work, couldn't be done. The truck sat, the whole way home the fog lights wouldn't work. Does this sound like the switch? The relay? This is driving me NUTS! I really can't see any trouble with the wiring. Any information will be greatly appreciated. Thanks in advance!

 

check your grounds, then id say the switch is faulty.

 

Sounds like a cheap kit and something is faulty..try replacing the relay and the switch and see if that does anything