NO TAIL LIGHTS!

[mhorgan]

One of my brake lights went out the the other day. Replaced the 3157 bulbs on both sides, checked all the lights and blinkers, evrything works, no biggie. Next day, blinkers are going 100mph so I figured the rear signal bulbs must have quit. I pull out the taillight housing to find that both stop lamp sockets burned out and now nothing in either housing works. I checked all the relays and nothing looked burnt. The third lamp over the cab works so I dont know what gives. Are all those lights on the same circuit so that the burnt sockets are keeping nothing else from working? Do I just have to replace the sockets?