7 pin cable
Due to a bit of age/corrosion, I have decided to replace the 7 pin plug/cable on the trailer. As I usually do when I am about to tackle something I haven't previously dealt with, I searched the net...
Forum Discussion
I just replaced the cord on my 5er for the same reasons. My initial thought was just to replace the plug, but since the plug is out in the weather, I would rather have a molded connection there, so I replaced the whole cord.
First measure your existing cord and get one the the same length. I got this cord from Amazon that comes in 8', 12', and 16' lengths. If your size is in between you can always shorten the cord.
The cord typically terminates in a standard 4" steel j-box. On my 5er, the box is under the pin box, and even though it's open to the elements on the bottom, it's well enough protected that the screws on the cover and cable clamp weren't rusted to death.
On my TT, the box was on the frame up under the Coroplast underbelly material, keeping it dry and protected from the elements.
It makes zero sense to add a second j-box on this cord unless the factory put the original j-box in a location that is impossible to get to. Otherwise, it's just a matter of opening the box, matching the colors, and connecting the new cord. Pay attention to the colors used on the trailer side and also how the breakaway switch is wired in. As you know in residential wiring black is hot and white is neutral, and in auto wiring red is hot and black is ground. Some trailer mfrs follow the black/white convention for 12v wiring, some follow the black/red, so pay attention to how yours is wired.
Typical 7-pin cord will have 2 #10 black/white wires for (+) and (-) charging lines, a #12 blue wire for the brakes, and 4 #16 wires for the lights. As Grit Dog says, the factory uses wire nuts and they work just fine.
First measure your existing cord and get one the the same length. I got this cord from Amazon that comes in 8', 12', and 16' lengths. If your size is in between you can always shorten the cord.
The cord typically terminates in a standard 4" steel j-box. On my 5er, the box is under the pin box, and even though it's open to the elements on the bottom, it's well enough protected that the screws on the cover and cable clamp weren't rusted to death.
On my TT, the box was on the frame up under the Coroplast underbelly material, keeping it dry and protected from the elements.
It makes zero sense to add a second j-box on this cord unless the factory put the original j-box in a location that is impossible to get to. Otherwise, it's just a matter of opening the box, matching the colors, and connecting the new cord. Pay attention to the colors used on the trailer side and also how the breakaway switch is wired in. As you know in residential wiring black is hot and white is neutral, and in auto wiring red is hot and black is ground. Some trailer mfrs follow the black/white convention for 12v wiring, some follow the black/red, so pay attention to how yours is wired.
Typical 7-pin cord will have 2 #10 black/white wires for (+) and (-) charging lines, a #12 blue wire for the brakes, and 4 #16 wires for the lights. As Grit Dog says, the factory uses wire nuts and they work just fine.
