Replacing Trailer End 4-Pole Connector That Has 8 Wires

Question:

What part do I need for a 4 way connector replacement on the trailer end. I snipped off the old connector and found that it doesn’t have 4 wires, but it has 8. 3 white, 3 brown, 1 yellow, 1 green. I did buy a trailer end connector that you place the wires end and snap the cover to replace, but I don’t think all those wires are going to fit in there. Again, is there a specific part that I need for this type of wire configuration? Thanks for any advice.

asked by: Carlos

Helpful Expert Reply:

For starters, a quick-fix type connector shown in your photo is typically a good choice for an emergency repair, but I wouldn't use it as a permanent fix.

It looks like your trailer wiring has 3 separate grounds and 3 separate running lamp circuits for some reason. This is kind of a strange setup, but if everything worked fine beforehand, there really wouldn't be any need to change that at this point. Your suspicion is correct, I don't believe all those wires will fit in there either.

For a long lasting, bulletproof installation that you won't need to mess with ever again (unless you pull off after forgetting to plug the trailer in and destroy the trailer connector), I'd recommend using a junction box like # 3375601101 as a good place to make all those connections. The wiring connections will be neatly done and protected from moisture and dirt/grime. To replace the actual 4-pole, I'd recommend a heavier duty option like the Wesbar # W787264 for a 4 foot, # W787268 for an 8 foot or # W787270 for a 10 foot trailer end pigtail. you'll also need ring terminals like part # DW05702-1 to make the connections.

This setup will make for a much cleaner and reliable installation. Should the trailer end pigtail become damaged in the future, it'll only take a couple of minutes to replace the pigtail, without needing to remove yards of electrical tape.

expert reply by: Mike L

Customer Submitted Photo
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Luis T.

7/15/2024

I have the same issue . How did you resolve this problem.

Mike L.

7/31/2024

@LuisT It was pretty well explained in the original Q&A, but essentially what you'll want to do is remove the existing connector on the trailer. If it's wired in the standard fashion, the green wire carries the right turn/brake lamp, the yellow carries the left turn/brake lamp, the brown handles the running lamps and the white is the ground connection. If you have non-standard wire colors, you'll need to use a 12V battery to apply power to each wire to see what illuminates so you can determine which function that circuit carries. If you have multiple wires, the junction box mentioned in the Q&A would make for a tidy and protected spot to make your connections. If you have any specific questions (or need some follow-up info) just let me know.

Brian

8/2/2024

So you'd connect all 4 whites and 4 brown wires on one terminal in the junction box?

Mike L.

8/3/2024

@Brian It would depend on their function. Typically white is the ground and brown is the running lamp circuit. The grounds would connect to one terminal, along with a jumper that's grounded to the trailer frame and the white wire from the trailer connector. The brown wires would attach to one terminal, which is also where you'd attach the brown wire from the trailer connector.