The brights work but not the regular headlights.

clean connections on bulbs

Why dont you start by checking the fuses for headlights refer to your owners manual for the location of the fuse box for your car. if the fuses are good then replacing headlight bulbs to both headlight assembly is your next step.If after replacing both headlight bulb you still have the same problem then you might have other electrical issues.

Most headlights have two different bulbs: one for regular/dim and one for bright. It's time to replace your headlights.

Replace the headlight bulb.

Check the headlight grounds. The battery could also be going bad.

if you know the bulbs are good then inspect the wires behind the light flexing over time the wires break

perhaps its the wiring leading to the lamp itself. I don't know about your car, but when i fixed mine, there are 3 lines leading to the headlights. perhaps the one leading to the regular light is probably cut or burnt. Try to have it checked with a car electrician if you're not comfortable fiddling with you car's wiring!

Hi David, first check your fuses some have seperate fuses for running lights and headlights, next make sure bulb connections are clean and connecting also check all parking and break lights if 1 is out in rear sometimes they wont work also is your switch on dash or steering colum, either way your coulkd have a faulty switch, HOPe this helps

sounds like your dim to bright switch went bad

check fuses connections and the switch