Headlight prob, maybe light sensor too

[cellar]

i'm having some problems with my headlights not working at all. Also what I noticed is that at night, when the sunlight sensor is sapposed to switch on and the dash lights get brighter, that doesn't happen. To get a headlight to work at all I have to turn the headlight dial all the way to the right (sorry, I really have no idea what it is called) and flip it to high beams.
Also as a back drop to this, I just had my alternator replaced at a dealer and when I took it in I had this problem but the light sensor was still working. I told them about it and they said they fixed it....night time comes and it is still the same. Any ideas?

 

[wuzzzer]

Low beam filament burnt out?

 

[cellar]

that might answer the low beam question, but i still dont know why the dash backlights won't turn on when it turns to night out.