Have no low beams but parking lights on that upper switch work fine. High beams are fine! Bulbs look good,checked filament continuity checked 40 amp fuse (lamps) under hood, checked both 10amp headlight fuses under dash and it all looks good. Got dark so did'nt check lamp sockets for power. Tomorrow morning! My guess is the switch. Ordered a nice used one. If no socket power, it's the switch, if there is, I'll buy bulbs! Somewhere I read that there's a relay under the dash. If anybody knows jump in! Will update.