Taillight Converter To Go From Combined Wiring System On A Miata To A Separate System On A Trailer

Question:

I have a Miata with a 4 pin plug and I am trying to connect it to a small cargo trailer with 7 wires 2 brown, 2 red, 1 white, 1 yellow and 1 green. this cargo trailer has amber colored lights for blinkers/emg. flashing lights. I dont know what part/parts i would need from you. Can you help?

asked by: David R

Expert Reply:

It sounds like your trailer has a separate wiring system and your Miata is a combined system. I recommend adding the Vehicle to Vehicle Tail Light Converter Item # 118158. This kit allows you to go from a combined system to a separate wiring system on a trailer to allow the lights to function normal.

The wires you have on the trailer are most likely split to each taillight from the front which is typically called wishbone wiring. What this means is when you wire the converter in place on the trailer, and it can be wired at the front near the plug, your two brown wires are the running lights. The two red wires are the brake lights. The white is ground. Green is right turn an yellow is left turn. I recommend testing the wires to make sure this is correct but this is industry standard. Once tested, wire the correct colored wires from the trailer to the converters same color single wire. The white wire can just be grounded to the frame.

If you do not have a 4 pole on your trailer I recommend adding the Mighty Cord 4-Way Flat Trailer Connector Item # A10-4404VP to the converter side connecting to your Miata.

expert reply by: Jesse M