Had my headlights also stopped working suddenly. We went through the switch, checked the wiring, u name it we did it. Then my mechanic decided to look at a relay. little silvery box that plugged into some other thing. unplugged it-and-- water! He shook both parts-the end of the wiring and the relay. Both had water. Turns out I have a leak that lets water get into the relay, So we replaced the relay-voila! got lights. I gotta search for the leak but meanwhile we put some plastic thing over the relay so water cant get in. Just another thing to consider; of course your issue may be totally different.