When my headlights come on either auto or manual they work for a couple of minutes then turn on and off a couple of times and then off completely. Seems they try to turn back on every minute or so but instantly turn off. I have visualy checked what wires I can see behind the switch for a short but looks ok. I was told there's a relay inside the switch itself is this true? If so are they prone to just not working properly? If the switch IS ok what is the best way to check for a short? The marker lights turn lights and fog lights are all working 100%.