Non-functioning Brake Lights

have you checked the bulbs ??? they have three filaments in them , its possible they could be burned out since your third brake light is working , keep it simple lmk

thanks

I have a 96 lumina with the exact same problem. Brake lights don't work except for the 3rd light in the window. Bulbs are good, emergency flashers work with the running lights on (uses both filiments in the bulb and most of the wiring), fuse good, Brake Fuse plug goes hot when fuse removed and voltmeter inserted.... Turn signal switch was a bit flaky but cleaned it out with contact cleaner and works better now... You say they have 3 filiments in the bulb? I only saw 2 ??? You sure about that? Maybe someone put the wrong bulb in (my mother's car) Thanks!