Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps

Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps

Item # C57674

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Curt Wiring - C57674
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This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet. Lowest Prices for the best wiring from Curt. Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps part number C57674 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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  • Reviews (221)
  • Q & A (138)
  • Videos (9)
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  • Why etrailer?

Curt Wiring - C57674

  • Wiring Adapters
  • Multi-Function Adapter
  • 7 Blade
  • 4 Flat
  • 4 Flat
  • Plug and Lead
  • Curt

This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet.


Features:

  • Adapts 4-way flat to both 7-way round and 4-way flat
  • Includes integrated test lamps which display proper connections
    • Shows if the wiring on your trailer isn't working properly - burned out bulbs, poor connection, etc.
  • Includes mounting bracket and hardware
    • Distance between vehicle mounting holes center to center: 2-1/4"


57674 Curt Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps



C57674 Installation InstructionsInstallation Details C57674 Installation instructions


California residents: click here


Video of Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps


Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Curt Wiring - Wiring Adapters - C57674 Review

Today we're going to be reviewing part number C57674. This is the Curt Wiring Adapter from a 4 way flat to both a 7 way round and a 4 way flat. The multi function vehicle end connectors are going to convert any 4 way flat end connector vehicle plug to a combination of a 7 way outlet, and that's also going to have the 4 pole flat outlet as well. It's going to include the integrated test lamp. You can see that it's going to have the display right here which is going to display the proper connections. This is going to indicate and show if the wiring on your trailer isn't working properly.

It's going to show whether you have burned out bulbs, poor connections, things that go along with that. It's also going to include your mounting bracket and all the hardware that you need to get the socket mounted to the bracket. It's going to come with four screws and it's going to come with the washers and the nuts that you need to get the bracket . or the socket mounted to the four connections there on the mounting bracket. To go over the functions of the wires real quick. You can see here that it's going to expose a 4 way flat connector.

This is designed to plug into your existing 4 way, and then it's going to have four more wires that are exposed. All the wires are going to have butt connectors on them. The white wire's going to have a ring terminal on it for easy connection, so those are already in place, they're already installed and ready to be connected. Your white wire is going to be your ground wire. This is to be grounded to the vehicle frame. The yellow wire is going to be the center pole of the 7 way connector.

It's normally used for connection to the reverse light circuit. Your blue wire is for the connection of the electric brake feed from the brake controller. Then your black wire is going to be the twelve volt wire and will need to be ran to the positive terminal of the vehicle battery. It needs to be ran through a forty amp circuit breaker. That is going to be sold separately.

You can find that right here on our website with part number PK54540. This wire will be used to maintain the charge of a trailer mounted accessory battery and/or breakaway battery. Those already have the easy connectors on them that way all you have to do is make a few connections, get some wiring. If you need the full setup for installing a brake controller, all the additional wiring, you can use part number ETBC7. That's a kit that we here at Etrailer put together to make it easier for you. You can find that right here on our website. I want to focus here on the 7 way connector. It's got a spring loaded lid so when it's not in use it's going to remain closed that way it's going to protect the connection points on the inside. It's got the indicators here on this side. Each light has a code right next to it. The first one's going to be twelve volt. That's going to be for the twelve volt hot lead. If that's connected correctly and working properly that will light up. BK is the output from the brake controller so if you do not have a brake controller installed this light will not light up. The back up, BU, is for the reverse lights. If this circuit is not connected on the vehicle it will also not light up. RT stands for right turn. TM stands for the running lights or tail and marker lights, and then LT stands for left turn. The overall dimensions of the actual socket here is going to be . the housing that goes around the socket, that's going to give us a measurement of three and three eighths by three inches. Once you have it ready to be mounted with the bracket all you have to do is run your wires through here. It's going to fit around that socket portion back here really nicely. It's going to go right through the appropriate holes. It's going to make sure that all the mounting holes line up, and then you're going to take your 4 way flat, it's got a couple grooves on it that slide into the bracket face. Once you have those on you just push it in. It's going to hold it right there for easy connection. You're going to have your 7 way round connector right here, and then right next to it you're going to have easy access to the 4 way flat. That's going to do it for our review of part number C57674. This is the Curt Wiring Adapter converting from just your 4 way flat to both a 7 way round and a 4 way flat system. .


Customer Reviews

Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps - C57674

Average Customer Rating:  4.7 out of 5 stars   (221 Customer Reviews)

This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet.

- C57674
by:

This is the second vehicle I have installed this adapter on. We tow a Coleman popup and another smaller trailer so we need both the 4-pin and 7-pin adapters. The test lamps are great to confirm that you have installed the wiring correctly. 401368



- C57674
by:

Shipped out very fast and arrived before the estimated arrival date.. install was super easy with the LED test lights. 609573



- C57674
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Worked great! Would buy again. 599093



- C57674
by:

I installed this 4 to 7pin adapter with the T-one harness 118449 and the Drawtite hitch on my 2016 Toyota Highlander. I think the install was 1st rate. This adapter allows me to connect either a 4 pin or 7 pin plug. Nice. Very simple to check out the installation with the test lights. Adapter looks rugged and well made. The 4 pin receptacle that slides into the bracket should have better retention though. Also I provided a picture of the 4 wire cable from the car harness to the adapter as it exits the storage compartment. I removed the grommet/seal. Made an X cut in the center. Forced the cable through it. Made a waterproof seal with RTV. 322171



- C57674
by:

Great product! Sturdy and weather-proof connections and wires! Easily installed. Thanks Curt and etrailer.com for an awesome item! 68991



- C57674
by:

I use both 4 pole flat and 7 pole connections on our trailers so this fit the bill. Here, I welded a bracket to use it on our Dodge Journey. 563114



- C57674
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Working perfectly after one year. Easy to install. Thanks for such a great product! 570896



- C57674
by:

Great product I used this to convert my 4-way harness to a 7-way + 4-way harness on my 2011 Toyota Sienna. Everything went really well. The only very small complaint I had about this product is the length of the white ground wire. It was too short to reach a good grounding point on the frame so I had to go buy some extra wire and connectors to extend it. Make that cable about 3 ft longer, and just provide the ring terminal and this would be a perfect product. Installing it makes me want to splurge on a tow controller and charge line... 135750


Comments

HiI have a toyota sienna 2011 and i want to tow a pop-up camper. Mine has a towing package. The camper is around 2400 lb. in your case do you think a brake controller is necesary?can you tell me What kind of cable do u buy to extend the white ground cable?Di d u buy the no drill tie bracket?

-- comment by: Aldo - 06/27/2014

5189
Comments

Aldo. We towed a popup trailer that was little less than that loaded weight without any issue. This was a one time rental for us. We towed up over Vail Pass in Colorado without any issue at all. The engine and transmission on the Sienna could tow a lot more weight, it is limited due to the suspensiontire rating.The only problem we faced is that when hitched we couldnt open the rear door of the sienna due to the trailer jack on the tongue of the trailer.If I was to tow regularly I would invest in a break controller, charge line, and a Weight Distributing Hitch. The main limitation in towing with a sienna is the hitch weight.No I didnt buy the tie bracket. The hitch I purchased 75696 had a built in bracket that this fit on perfectly just had to get a few screws/nuts for it.I just bought some 12 guauge auto wire at autozone.

-- comment by: Daniel S - 06/30/2014

5220

- C57674
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crimp connectors should be the heat shrink type 569841



- C57674
by:

The bracket was too wide for the OEM hitch and cover on a 2013 Highlander (see photo). I had to grind down part of the the bracket so it would clear the plastic cover. The top two mounting screws did not line up. I had to elongate one of the holes. The 4 pin connector merely slides into the side of the bracket, rather than fitting in like a grommet, so I'll bet it comes out one day. The wiring on the back of the 4 pin connector is visible when looking at the side of the bracket, making for a less than clean look. 82915



- C57674
by:

I really liked the idea of having the LEDs to let me know if I was having any problems with the wiring harness, but I did find a problem with it. I installed the wiring harness myself, using the instructions on the website, but after connecting everything I realized that the LED for 12v power is always on. It is not switched by the key, so although an LED should have low draw, this might not be a good idea on a work truck that stays parked for long stretches. 80885


Comments

I am still very happy with this adaptor, but I did put back in the plug on my brake controller so I could unplug it when the trailer was not connected, the brake light was on, and I disconnected the continuous 12v. Also, make sure your 4 wire connector is clean or you might have dim lights. Although the LEDs are useful, I found a plug in tester to be more accurate because of the false brake signal I was getting.

Chris H - 05/19/2014

4322

- C57674
by:

I recently had a receiver hitch installed on my 89 Silverado and the wiring was merely zip tied to the safety chain connection. Well that didn't sit well with me. I wanted a more permanent wiring connection point. So I purchased your 4 flat to 4 flat and 7 way plug and installed it. So far so good. The installation turned out perfect and it looks good. The test lights are a great thing as well. I couldn't be happier. 420882


Comments

Perfect. The only issue I had was the 4 flat didn’t stay in the bracket but that was easily remedied with a couple of holes and some safety wire. Other than that I’d say u have one of the best setups you could ask for.

Lawrence L - 08/16/2018

42419

- C57674
by:

Great customer service on-time delivery super fast shipping product was just as described works well and just what I was looking for. 452971



- C57674
by:

2013 Dodge Durango Looks great. Nice and clean installation. 134266



- C57674
by:

Last project built. Used etrailer for almost all parts, including the 7 pin wiring harness. Friend wants one now so started another one. I will be getting all the parts from etrailer... 486395



- C57674
by:

Best thing I did for my Pop Up camper. It allowed us to use the electric brakes. We do not even notice the trailer back there any more. Only thing is the little red light stays on all the time (like it is supposed to) so people are always letting us know we have a light on. 724919



- C57674
by:

Great price. Well built. Has everything I need 720317



- C57674
by:

Perfect, easy, prompt 713104



- C57674
by:

Works great 707974



- C57674
by:

Ordered one plug . Etrailer informed me that plug might be awhile. So they suggested another plug. Received new equipment, Installed new plug works great. Thanks for helping me out. Thanks Terry 704519



- C57674
by:

I received the wiring harness and found it to be well constructed. I installed it onto the truck easily enough, with just 2 bolts to attach the frame to the truck hitch and 4 supplied bolts to attach the plug harness to the frame. The connector worked perfect however, the wiring harness was about 2 inches to short. In order to get the connectors to come together, I had to re-route the truck's wiring harness. It was not so easy to accomplish but I was successful. Why does the trailer harness have to be so short? Maybe it works for some applications but didn't work for my 1992 GMC Sierra. There were 3 other wires that had to be manually attached. There was a positive 12 volt wire, a back-up light wire, and a electric trailer brake wire. You didn't supply a wiring diagram with the package. I had to guess which wire was what. Fortunately I was able to get the wiring descriptions from your website, but, you should never ship any kind of electrical device without a complete wiring diagram and instructions for assembly. 698339



- C57674
by:

This is second of these auto 7 pin plugs on two cars. You just plug into the 4 pin plug that connects to car and add a 12 volt power, brake controller and ground. The best part for me are the diagnostic indicator lights that will help trouble shoot light or brake controller failures if they ever happen. It is also nice to have a 4 and 7 pin connector available. 673513



- C57674
by:

Product was exactly what I was looking for. Have used it already and performance is just as expected. Easy installation. Would recommend this product. 669673



- C57674
by:

Great product just wish it came with some self tappers for the mount. 669481



- C57674
by:

Installed this item together with item 118379. Perfect fit and I like the built in test lights. Another great product sold by etrailer. Thanks again ! 667152



- C57674
by:

Wired new Dodge Durango. Dealer wanted 1495.00 for new hitch and wiring. etrailer got me the parts needed in 2 days and vacation didn't have to be postponed. Oh yes the total bill was 220.00 vs 1495.0 thanks etrailer. 652817



- C57674
by:

exactly what I needed, adapts my 4 pin wiring to the 7 pin connector 642010



- C57674
by:

Wiring fit well. Delivery was quick. Videos very helpful with installation. 641737



- C57674
by:

Ordered my hitch for my truck yesterday afternoon and it arrived this afternoon. Great Service! 637551



- C57674
by:

The initial adaptor I ordered was out of stock and the website didnt state that. I contacted the company AMD they immediately added a similar adaptor and I still recieved this item on time. 621855



- C57674
by:

This purchase of C57674 is to replace a prior purchase (Fall 2015?) of the same item, WHICH FAILED! The failure was the result of a short in the wiring to the LED indicator lights. I generally like the product and it did work well for 3+ years. The adapter allows you to retain the "FLAT 4" connector and also gives the option to have a 7 PIN RV connector. The product seems to be well constructed (Taiwan) and I would recommend it. 608098



- C57674
by:

Works as expected, was missing a few nuts had to buy some to put the bracket on. 604746


Comments

The trailer connector adapter includes the hardware for mounting the connector to the bracket, but not the screws or bolts for fastening the bracket to the vehicle, as the correct hardware for that task will depend on what the bracket is being attached to.

-- Mike L - 02/13/2019

49461

- C57674
by:

This is a replacement to one I purchased about a year ago. The first one shorted out, not sure why Not happy with quality, bracket rusted out after 1 year along with mounting screws 604437



- C57674
by:

Great products and great customer service! Definitely will use them in the future. 600824



- C57674
by:

This wiring harness completed my 2017 silverado with a factory hitch package and was easy to install. i saved hundreds on installing myself with the new class 4 hitch. very happy...the wiring harness is factory quality... 594206



- C57674
by:

Quick delivery correct part. Very happy with service and quality of product. 584686



- C57674
by:

Used as an external connector with the converter kit. Looks and works great. 581375



- C57674
by:

The test lights are a nice touch and it looks sleek all mounted up. Definitely worth the extra. 579087



- C57674
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Nicely made. The indicator lights on it are super useful. 569166



- C57674
by:

Looks good, easy to install. 555328



- C57674
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Product worked fine 554613



- C57674
by:

Easy to hook up and performs as designe d. 550261



- C57674
by:

Works great 550038



- C57674
by:

The 4 Pole to 7 Pole adapter works great, and the indicator lights signal you that every pole is receiving power when connected to the trailer. This will be great for diagnosing a burned out bulb. I utilized a piece of sheet aluminum to mount the adapter to the underside of my Volvo XC70 bumper cover, and it is working great as installed. Was a great buy and a good value. 542151



- C57674
by:

Works great so far. 539853



- C57674
by:

excellent product ,easy to install 516505



- C57674
by:

good price, simple install, and works.. 513005



- C57674
by:

Got the part faster than expected. Although no directions, install video on their web site made putting on my truck easy to figure out. Just wish it came with a couple of self tapping screws for the mounting bracket. Nice product, it was perfect solution for me, so I don’t have to get the expensive factory 7-way/ 4-way adaptor. 512234



- C57674
by:

Purchased this along with part#Hm42115. Super easy install, everything works great. 2000 Dodge Ram 1500 without the 7-way plug. Called customer service before I started and they told me exactly what I needed and got it ordered 509996



- C57674
by:

easy to install 499204


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Ask the Experts about this Curt Wiring

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  • Installing a 7-Way Trailer Connector on a 2017 Subaru Outback Wagon
  • That is correct for your 2017 Subaru Outback we only carry 4-way trailer connectors that are a direct fit. However, once you install the 4-way it can be converted to a 7-way, if that's what your trailer needs. Of the 4-way connectors for your Outback I recommend the Tekonsha # 118467 because we always have great success with them. To install the harness you'll need to locate the factory connector in the Subaru's rear cargo area. Then install the included fuse. I've linked an install...
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  • Installation of 7-Way and Brake Controller on 2016 Ford Expedition with Factory 4-way
  • For your 2016 Ford Expedition, I recommend the Prodigy P3 # 90195 for a brake controller due to the ease of use and reliability. It is a customer favorite because of the LCD screen and diagnostics as well as preset boost options. You will then use custom wiring adapter # 22292 which connects to a factory harness behind your dash. I've attached installation instructions to assist. As you stated, there is a blue brake wire and there is also a hot lead wire that is orange or red. This...
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  • Recommended Towing Components for 2018 Hyundai Santa Fe Without Trailer Hitch, Wiring, or Controller
  • For your 2018 Hyundai Santa Fe, the Draw-Tite Max-Frame Trailer Hitch Receiver - Custom Fit - Class III - 2" # 75776 you chose is an excellent option. It will be an easy installation using the existing weld nuts and the hardware that comes with the hitch receiver. I've attached the installation details to assist. For your wiring, the Tekonsha T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector # 118269 is the best fit and will connect to the factory...
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  • Adding Trailer Brakes to a 3.5K Dexter EZ Lube Axle and Brake Control/7-Way on 2016 Subaru Outback
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  • Curt Adapter # C57674 and Tekonsha Prodigy P2 and P3 Operation
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  • Parts Needed to Add 7-Way to 2014 Toyota Sienna for Towing
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  • Trailer Connector Needed That is Compatible with the Curt Adapter # C57674
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  • Brake Controller Recommendation for 2018 Ford Edge Titanium with Tow Package
  • There isn't a quick-install brake controller port on a 2018 Ford Edge Titanium with a tow package for installing a brake controller. In fact the only brake controller we offer that can fit the versions of the 2018 Ford Edge Titanium with the tow package and 7-way is the Prodigy RF part # 90250 which is a wireless controller that mounts on the trailer. Let me know when you pick out the Edge and what trailer wiring it has at the rear of it and what brake controller you'd like to install...
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  • Adding a 7-Way Trailer Connector to a 2007 Toyota Tacoma
  • In order to install a 7-Way trailer connector on your 2007 Toyota Tacoma you would first need to install a 4-Way and then hardwire in a 7-Way using # ETBC7. There isn't a plug-in 7-Way available for your truck. For a 4-Way you are correct, they do plug in-line with the vehicle tail light wiring. You can use # 118496. You would then install the ETBC7 which also includes provision to install a brake controller such as the P2 # 90885. I have included some links that show and explain the...
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  • Brake Controller Wiring Needed for 2013 Ford Escape with Prodigy Controller
  • Since you have a 7-Way # C57674 you will only need a few more components to complete a brake controller install on your vehicle. For a wiring kit to install the brake controller to the 7-way you would want the Wiring Kit for 2 and 4 Brake Electric Brake Controllers # 5506. This will provide the power source and ground for the wiring for the brake controller. You will need to test the wires from the brake pedal switch of your vehicle to find a circuit that has voltage when the brakes...
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  • 7-Way Trailer Connector for 2011 Toyota Highlander
  • If all you are needing to do is provide lighting functions for the camper (directionals, running lights and brake lights) and if your Highlander already has a 4-pole trailer connector, you will only need a 4-pole to 7-way Adapter, part # 37185. If you do not already have the 4-pole connector, you will additionally need the T-1 Connector, part # 118449. If your camper has electric brakes, you will need a brake controller. I would recommend the Tekonsha Prodigy P2, part # 90885. The...
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  • Recommended Wiring When Adding 7-Way Trailer Connector To 2016 Ford Escape
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  • Adding 7-Way Trailer Connector to 2014 Toyota Tacoma without Factory Tow Package
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  • Does the Prodigy RF Brake Controller Need Brake Output and Reverse Lights Circuits to Work
  • Since you are using the Prodigy RF brake controller # 90250 you will only need to have the 4-Way plugged into the adapter, the white wire grounds to the vehicle frame, and the black wire needs to have power because that is where the RF gets its power. The blue and yellow wires on the adapter, # C57674, will not be used for the RF. But if your trailer has an electric reverse lock out then you would have to attach the yellow wire to a reverse light wire on the vehicle The black wire...
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  • Indicator Lights on Curt 4-Pole to 7-Way Adapter
  • When fully installed, all the lamps would be lit as each function was activated. The BK or brake would not be lit, as you do not have a brake controller installed. The BU lamp would only light if the vehicle transmission were in reverse and that yellow wire was tapped into the circuit feeding the reverse lights on the vehicle. The 12V lamp would only light if the black wire was attached to the positive battery terminal. The 12-Volt circuit should be circuit protected using a 40 amp inline...
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  • Why Would 12 Volt Power Circuit of 7-Way Tester be Active all the Time
  • The 12 volt trailer accessory circuit of your 7-way is ran directly to the positive post of your battery which means this circuit is active all the time. This is why the light is on currently. To prevent this you'd need to install an isolation solenoid so that it only comes on when the vehicle is on. Now with that said whoever installed your brake controller did not install it correctly. The brake controller should have no affect on your vehicle brakes and if it does you need to have...
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  • Adding a 7-Way and Brake Controller to a 2015 Ford Expedition with Factory 4-Way
  • From what we have found the 2015 Ford Expedition that came with a factory 4-Way connector will need a little bit of hardwiring to install a brake controller and 7-Way connector. You will need # 37185, some wire (more on that later), a brake controller, and a brake controller wiring harness. The 37185 will plug into the 4-Way. Then you will ground the white wire to the frame. That will leave a blue wire, black wire, and purple wire. The purple wire is for reverse lights so if the trailer...
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  • Where Does a Brake Controller Plug Into on a 2014 Toyota Tacoma
  • Did your 2014 Toyota Tacoma come with a factory installed 7-Way trailer connector? If so the factory brake controller connector should be located underneath the dash, to the left of the steering column, taped to another harness near the emergency brake pedal. It is also possible that it is behind the kick panel adjacent to the emergency brake pedal. For a brake controller I recommend the P2 # 90885 because it is easy to set up and use and it is reliable. And you would use wiring harness...
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  • Troubleshooting Curt Triflex Trailer Brake Controller Function
  • Curt TriFlex Trailer Brake Controller # C51140 has two LED dots as you mentioned. One is for power standby mode and the other is for trailer connection. I've attached a video as well as the installation details that will help with deciphering any codes. If you are not getting a trailer connected signal when connected it may have to do with corrosion and I'd begin with cleaning the connections. If there is still no connection, I'd use a circuit tester like # PTW2993 to check for any...
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  • Two Ways to Install a Trailer Brake Controller on a 2008 Dodge Ram 1500 with Factory 4-Way Wiring
  • There are 2 ways you can install a brake controller. On a 2008 Dodge Ram with a factory 4-Way, we usually recommend a hardwire installation using a 4 and 7-Way installation kit # ETBC7. It includes an adapter that is just like # C57674 but it also comes with everything else you will need to complete the installation of your P2, # 90885. However, there is an alternate method which I will also explain after the ETBC7 explanation. The 4-Way on your truck has the lighting functions for a...
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  • Wiring Diagram for the Curt 4 Pole to 7 Pole Adapter # C57674 And Wiring for Trailer Brakes
  • The wiring for the Adapter 4 Pole to 7 Pole and 4 Pole, item # C57674, is wired as follows. The white wire is grounded to the vehicle frame as you have indicated. The Yellow wire is the center pole of the 7-Way connector and is normally used for connection to the reverse light circuit. In your case you will not need the yellow wire. The blue wire is for connection of the electric brake feed wire from a brake controller. You will need a brake controller in your Sienna to activate the...
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  • 2004 Ford E350 7-Way Recommendation for Connecting to Vehicle Wiring Under Van
  • You will want to test the wiring you have found under your van to see if it is active. You will want to use a circuit tester like the part # PTW2993 to check the ports for voltage as you apply the different turn signal functions. If it is active then you could wire the part # C57674 to the wires. You would need to cut the 4-way off and then run a length of 7-way wiring # DW04914-1 sold by the foot to connect the wiring to the 7-way.
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  • Options for Converting Factory 4-Way to 7-Way on 2014 Ford F-150
  • The Curt Adapter, # C57674, is exactly what you will need to add a 7-way to your 2014 Ford F-150. Installation will be fairly simple, just connect the 4-way on the adapter to the 4-way on your truck and then connect the remaining wires to the corresponding wires on the back of the factory plug. Unfortunately a 7-way connector that will plug directly into the vehicle wiring is not available.
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  • How to Install a 7-Way Trailer Connector to Add a 12 Volt Power Lead to a Trailer
  • It sounds like you are missing a wire for the running lights on your trailer. Trailers that are wired for lights will have 4 or 5 wires, one for right stop/turn, one for left stop/turn, one for ground and one, possibly two, for running lights. Does your trailer have functioning turn signals, brake lights and running lights? If the two brown wires you mentioned are separate wires from the green and brown and yellow and brown wires, then you have a wishbone harness, which means you have a...
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  • Parts Needed to Install a 7-Way Trailer Connector on a 2006 Toyota Tundra with 4-Way Connector
  • I see you already purchased the Curt 4 Pole to 7 Pole Adapter, # C57674. This is the appropriate adapter to convert your 4-way trailer connector to a 7-way trailer connector. Since you do not have any turn signals or brake lights, I recommend testing your original 4-way trailer connector with a circuit tester like part # 40376 for those functions first. I have attached a demonstration video showing how to use a circuit tester to test a 4-way trailer connector for you to check out. I also...
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  • BK LED on Curt 7-Way Adapter, Part # C57674, Remains Lit Even Without a Trailer Connected
  • If you do not have a proportional brake controller (but instead have a time-delay type) the LED being lit could indicate a short to the controller output circuit. In some cases the manual brake switch on your controller may be partly engaged; this would also cause a signal to be sent to the 7-way BK LED. You can correct this by flipping the manual switch on and off several times to clean the contacts. If you are using a proportional type brake controller such as the Prodigy P2, part...
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  • What Does the Yellow Wire Do on Curt 4- and 7-Way Adapter # C57674
  • I have included a link to a help article that explains the various connections that need to be made under the hood/vehicle to install a 7-Way and brake controller on your 2002 Chevy Silverado. On the Curt 4- to 7-Way adapter # C57674 the loose yellow wire is for reverse lights. If the trailer does not have reverse lights or an electric reverse lockout (on a surge coupler) then this circuit is not needed. Otherwise you will tap into a reverse light wire behind one of the tail lights...
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  • 12 Volt Warning Lights Stays on After Install 4 to 7-Way Converter on 2015 Honda CR-V
  • The 12 volt circuit is supposed to be always active on the 7-way after it's wired. If you are experiencing some other problem let us know and we will do our best to come up with a solution.
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