head light swith or dimmer?

my 97 tahoe head ligts quit. i still have day time lights and running lights, but lose everything with head lamps on. also no dimmer or brights, is it the head lamp switch or dimmer switch?

Any information would be helpful. thanks!

does you tail light work? There is a black relay under the dash to the right side of steering colom. If its bad the headlights or taillights will not work.

Tail lights do work. Can both low beams go out at once?