2002 Dodge Caravan only 3rd tail light lights

I have replaced ed the harness checked the bulbs and the Fuses the turn signal works and so does the reverse light I am thinking after reading on u r sight that it might b the turn signal switch interfering with the brake lights it's 2002 dodge grand caravan el the rear lights have 6 wires coming in but only 4 plugs would this b a sign that the turn signal switch does interrupt the brake lights and needs replaced