I got this from e-trailer:
Question:
Hi, I am trying to hook my boat trailer with 4 pole flat to my 2000 Monaco Diplomat motorhome with a 6 pole rectangular plug. I cant find an adapter that goes from 6 rectangular to 4 flat. Hoping you can help. Thanks
asked by: John W
Checkmark Icon Helpful Expert Reply:
The 6-Way square trailer connector is not used by a lot of trailer manufacturers. A lot of Jayco trailers may have them but mostly you come across the 4-Way flat, like what you have on your trailer, and the 7-Way blade for RV applications.
What I recommend is to convert the 6-Pole on the Monaco to a 4-Way. You can do this very easily by removing the 6-Way plug, and then testing the wires for function using a circuit tester like # PTW2992 if needed before installing them in a new 4-Way, # HM48030. The 4-Way vehicle end functions will be oriented in the 4-Way as follows:
Exposed pin = ground (white wire on harness)
Next pin = running lights (brown wire on harness)
Third pin = left turn and brake lights (yellow wire on harness)
Last pin = right turn and brake lights (green wire on harness)
The other wires can be taped up and stowed out of the way.
Since so many more applications use the 4-Way flat, this will be the ideal option. But, if you do not want to remove the 6-Way on the RV, you can make your own adapter. You will start with the 6-Pole Square Trailer Wiring Connector Kit, # 37995. Plug the trailer end into the connector on your RV, then use a circuit tester like # 3808 if needed to test each wire.
Next, use the vehicle end in the Quick Fix(TM), # 48195, and insert the wires as described above. The other wires you can tape up because they will not be used by the 4-Way. Once you have made all of the connections you will have made your own adapter.
It sounds like the red and black are power wires. The rest are operational for turn, brake, running, etc. they suggest testing but you will need to hook up a ground first.
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