No brake lights- help troubleshoot
 

I have an '87 S and the brake lights don't work and there is no voltage at the brake lights. The fuse is ok but I only show 5 volts at the fuse. I also have 5 volts at the brake light switch on the black & green wire. When I short the two brake light wires together the lights don't work and there is no voltage at the black & green brake light switch wire. Any idea what is going on here?

Nevermind, I got it fixed- damn grounds.