Light out Warning On

[pguard]

I have a 94 C280 and just last week when ever I turn on the headlights, the yellow warning light (Light burned out) comes on. When I step outside the car and look around it looks like all the lights are on to me. During the day time it doesn't come on, but when I turn the lights just 1 positon to the right (parking lights) the yellow light comes on and stays on when I turn it all the way to turn on the head lights. Any ideas?
Thanks in advance
Greg