I have checked the forums for a similar problem but everyone else seems to have no brake lights or the brake lights will not go off. My third brake light on an 05 Sable wagon just doesn't go on when I hit the brakes. Took the light off the car and inspected the bulbs. They were fine so I reinstalled them with some dielectric grease to make sure they would not corrode although all the metal looked fine (no rust). Since the regular brake lights work fine I believe the problem must be in the ground wire between the lights and the car body where it connects? Has anyone had a similar problem and if so where was the problem?