1985 Chevrolet Blazer tail lights Switch change

First check your fuse as that may be blown. Then before replacing switch see if the brown wire going in back is getting power or not. If it does check the ground in back on frame. If not unplug the dimmer switch if it's on the floor and seeif it works. If not then replace the switch. To remove the switch pull the knob out, and reach under dash to back of switch and push down spring loaded button then pull the knob out. Take the screws off of thetrim plate then usea flat bladed screwdriver to remove the ferrule nut on switch. Pull I t out from back unhook electrical then reverse for reassembly