Junction Box With 7-Way Plug To Avoid The Use Of A 7-Way To 4-Way Adapter

Question:

I have a 7 pin connection on my 91 Tundra and a flat 4 on my vintage camper. I want to eliminate the adapter and install a connection junction box on the tongue of the trailer. I would like to purchase a box that comes with the pre-wired 7 pin connector. Can I just connect my 4 trailer wires to 4 specific posts in the box? And then just leave the other 3 open? Or would I need to install a jumper connection or something? I think what I want to do is wire the connections in the box to produce the same results that the adapter produces? Does that make sense?

asked by: Don R

Helpful Expert Reply:

Yes it makes sense and it is possible to just use a junction box with pre-installed 7-Way to connect your 91 Tundra with 7-way to the 4 flat on your trailer. I recommend Epicord 7-Way Molded Trailer Plug With Junction box part # 277-000141. The molded 7-way plug connects to the Tundra and you can just wire the left turn/stop, right turn/stop, tail/running light and ground to the corresponding circuits in the junction box.

Wire gauge and function of junction box:

White (ground): 10 gauge
Black (12V power): 10 gauge
Yellow (reverse/auxiliary): 14 gauge
Red (left turn and stop): 14 gauge
Green (tail and running lights): 14 gauge
Brown (right turn and stop): 14 gauge
Blue (brake): 12 gauge

It is not an issue to leave the other 3 circuits open. If you need wire I recommend part # 10-1-1 for 10 gauge, part # DW02413-1 for 14 gauge and part # 12-1-1 for 12 gauge.