How To Wire Replacement Vehicle 7-Way Trailer Connector Socket

Question:

Matching colors and getting power to the trailer.

asked by: James A

Expert Reply:

It looks like you're replacing the 7-way on a vehicle. The best practice is to wire a replacement trailer connector like # PK12-707E for the socket only or # PK11898 if you'd like a socket with a quick disconnect pigtail by function and not wire color.

If you go with the socket only, the brown wire typically carried the running light circuit, and would attach to the terminal in the 1:00 position when looking at the back of the connector. The left turn/stop lamp is usually carried by the yellow wire, and is in the 3:00 position, the ground connection is usually carried by the white wire in the 5:00 position, the brake controller output is carried by the blue wire and connects to the terminal in the 7:00 position, the green wire carries the right turn/stop lamp in the 9:00 position, the 12V feed to the trailer can be carried by a black or sometimes an orange wire and connects to the terminal at 11:00 and the reverse lamp circuit connects to the center terminal. I'd recommend activating each taillight function on by one as you test the wires to confirm. The 12V feed should show a constant 12V if it's connected.

If you use the # PK11898 pigtail, that uses a different color code scheme, red for left/stop, white for ground, blue for brake output, green for right turn/stop, black for 12V feed, brown for running lamps and yellow for reverse lamps.

What you show in the photo looks like it's been messed with quite a bit over the years, so I'd highly recommend verifying things with a circuit tester like # PTW2993. I've linked so some wiring diagrams that you'll likely find helpful.