Having no luck with tail lights....
The only thing in common to all those lights is going to be the ground.
If you have an electrical tester, you can test between the hot contacts at the socket and the ground to see if you have any voltage. If not, (which would correlate to the bulbs not working) then test between the hot contacts and then a bare piece of metal on the car. If you get voltage there, then you know you have a cut/disconnect in your ground. If not, then the lights just aren't getting power.


