[wldcat10]

Hey guys I need help! I was checking out my water pump on my '70 c-10 the other day just before it got dark out. So I checked it and took it for a spin around the block. When I went to turn on the headlights, they didnt turn on! All other lights are working. Parking lamps, tail lights, and side markers are all on and working. Only my headlights are out. I've never had this happen and don't know where to start? Any Ideas on what it could be? Any help is appreciated, thanks!