7-Way RV Trailer Connector Wiring Diagram


trailer connector wireing diagram. need to know which color wire go to which post.


Expert Reply:

When wiring a trailer connector, it is best to wire by function, as wire colors can vary. We have an excellent wiring diagram on our website, I will provide you a link so you can look at it.

If you are looking at the inside of the trailer connector where the wires mount to the terminals starting at the top and rotating clockwise:

1:00 is Black and 12 volt power
3:00 is Green and Right Turn and Brake
5:00 is Blue and Brake Controller
7:00 is White and Ground
9:00 is Yellow and Left Turn and Brake
11:00 is Brown and Tail and Running Lights
Center is Purple and is Optional Reverse

I recommend using a circuit tester like part # 40376 to verify your connections.

I attached a picture to that shows how the connector should be wired.

Click to Enlarge
Click to Enlarge
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Follow up Questions

Don M.

I have a 2020 3500 chev pk-up with factory brake control & wiring. I have no power to any light pins on 7 wire plug w/tester. However i have 3 trailers 2 work fine 1 don't. All 3 trailers work on 2011 pk_up. 77140

Reply from Chris R.

If aren't reading any power to the signal light pins on your Silverado's 7-Way, my first thought would be a blown fuse under the hood. Check your owner's manual for the appropriate fuse locations and replace them if needed. I'm not quite sure what you meant by 2 of the trailers working though - are you saying that their lights DO work when hooked up to the Silverado? 62730


I think you meant well but your wiring instructions are very confusing. Your instructions state: "If you are looking at the inside of the trailer connector where the wires mount to the terminals starting at the notch at the top and working clockwise". I assume this means looking at the back of the connector where the wires attach, right? So it is the image on the right. Then you say with the notch at the top black 12v power is at 1:00. This is very confusing, the image you include has the notch at the bottom. So if you rotate so notch is at the top then 1:00 per the image is Blue brake controller. Seems like either the image, the notch or your instructions are not consistent. 76457

Reply from Chris R.

I see what you're saying. I believe Andi was referring to the trailer-side 7-Way with the written locations (the second image). You're right though that this is when looking at the back of the connector (where the wires actually attach). 62392

Reply from Tom

But the notch is not at the top in the image, it is at the bottom.... 62404

Reply from Chris R.

I see now! I'm really sorry for the confusion. I updated the page to avoid mention of the notch, which is in fact at the bottom when looking at the diagram. 62512

Reply from Tom

Appreciate it, thank you .... 62513

Joe F.

No power at auxiliary power blade. Any suggestions ? 75642

Reply from Chris R.

More times then not when the 12V pin on a 7-Way isn't active it's the result of a blown or missing fuse under the hood. Check your vehicle's owner's manual for the fuse locations and make sure the one connected to the 12V trailer circuit is present and in good condition. Let me know if it looks good or replacing it doesn't help. 61788


When I put the turn signal on it flashes all the lights on the trailer also there is no running lights and we have but dont seem like the Brakes on the trailer wont Engage 72307

Reply from Chris R.

It sounds like you've got a few issues going on. I'd start by testing the 7-Way (or 4-Way if that's what you have) on the tow vehicle with a circuit tester. Make sure you're getting power at all the appropriate pins with the corresponding function activated (turn signals, brake lights, etc). This will tell you where the issue actually is - the vehicle or the trailer. From there inspect your wiring to make sure all the connections are correct and look for any frayed or exposed portions that need to be replaced. Look at the connector itself (both on vehicle and trailer) for any debris or corrosion that needs to be cleaned out. With regards to the actual brake function on the trailer - are you using a brake controller in the vehicle? Let me know what you find and we'll go from there. 59261

Janine M.

Trailor brakes are locking up. hook up is right. please help. 1990 Fleetwood prowler lynx 70568

Reply from Chris R.

I would start by testing the brake output pin on your tow vehicle's 7-Way (5 o'clock position) with a circuit tester. See if you only get power there with the manual override activated on the brake controller. If you're getting power at any other time then there's a short somewhere between the controller and 7-Way. You would just need to inspect any wiring you can along the vehicle to check for any exposed, pinched, or otherwise damaged portions that need to be fixed. If the 7-Way tested normal then something is going on with the wiring on the trailer side. Inspect the trailer's 7-Way itself for any corrosion that needs to be cleaned out and then inspect the wiring leading back to the brake assemblies. Let me know what you find and we can go from there. 57587

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