My signal light would work sometimes... but, the brake light would short out also which is a definite pull-me-over. I looked at it and it seems that there is a circuit board type set-up from the plug to the bulb. It had melted. Looks like they are so close together that they grounded out. So, what I did was strip about 1 1/2 inches off two pieces of wire into the corroded contacts pushed the replacement bulb back into the lens after lining the wires up with the connections. Both pieces were about 4 inches each. I spliced them into the white wire with the orange stripe in the harness which was the trace of my problem. Taped the wires after a little solder and presto! My tail lights work again! You could go the expensive road and replace the entire lens. The plug and circuit board on the lens don't come off so you would need to replace everything. I thought it was either the switch or wiring because the signal light would work from time time. Simply bypass the problem all together to avoid extra costs.