The third position should should turn on the headlights, if you can´t get it into third position it´s possible there´s crap in the locking mechanism so spray some compressed O2 into it and see if that cleans it out. Also the locking system comes off pretty easy so you may want to remove it for cleaning. If it goes into the position but just doesn´t turn the light on check the bulb. If you run the bike without a batter to regulate the voltage at higher RPM´s it will blow lights and possibly fry some wiring. So check to make sure the bulb isn´t just blown. Then I would check the fuse box.