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Vehicle to Vehicle Taillight Converter To Power Caps 3rd Brake Light


I am looking for a harness I can plug into my 4 prong trailer plug that will power my caps 3rd brake light . I have a round plug and a 4 prong, and I never use the 4 prong so I thought I would if its possible .. Truck is a 2006 ford 150 supercab XLT 57 bed


Expert Reply:

You will need to install the Vehicle to Vehicle Taillight Converter # 118158. This converter will work with the caps 3rd brake light. LED lights are only a concern if they are on the vehicle and the converter draws power from them.

The converter can not be plugged as a part of the 4-way because it services the traditional functions such as brake, turn and tradition tail lights. Since you need a 3rd brake light, you will need to splice into the wiring to ensure it functions properly.

The Vehicle to Vehicle Taillight Converter # 118158 separates the signals so the third brake light will only illuminate when the brake pedal is pressed. You need to connect the combined left turn and brake light circuit on your truck to the input side of the converter's yellow wire and the right turn and brake light circuit to the input side of the converter's green wire. Then ground the white wire on the input side. On the output side you can just cap off the green and yellow wires because they're now just the turn signal function and they are not needed. The red wire on the output side is connected to the third brake light on the cap.

For all connections I recommend using the Deka Heat Shrink Butt Connector, # DW05745-5. The heat-shrinkable nylon insulation allows for adjustability and provides durability.

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