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Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter

Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter

Item # 20036
Our Price: $19.98
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Trailer Wiring
Shipping Weight: 0.31 lbs
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Tow Ready Plug and Lead Trailer Wiring - 20036
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Trailer wiring adapter changes the 4 pole flat on your vehicle into a 5 pole flat. Great Prices for the best trailer wiring from Tow Ready. Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter part number 20036 can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (249)
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  • Videos (5)
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Tow Ready Trailer Wiring - 20036

  • Wiring Adapters
  • Single-Function Adapter
  • 5 Flat
  • Plug and Lead
  • 0 - 5 Feet Long
  • 4 Flat
  • Tow Ready

Trailer wiring adapter changes the 4 pole flat on your vehicle into a 5 pole flat.


  • Length of harness: 20"
  • Length of blue wire: 60"

The blue wire gets spliced into the reverse light wire on the vehicle which is easily done with the included quick splice wire connector.

20136 Tow Ready 4 Pole to 5 Pole Trailer Wiring Harness

California residents: click here

Video of Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter

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

Video Transcript for Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter Installation - 2009 Nissan Xterra

Today on our 2009 Nissan X-Terra we'll be adding the Tow Ready four pole to five pole trailer wiring adapter, part number 20036. With the vehicle already equipped with a four pole connector, we'll be adding the four to five pole adapter, which will plug directly into our four pole connector with additional blue wire connection. This blue wire connection will be the reverse taillight wiring feed. To start, we'll go ahead and open up the rear tailgate where we'll remove the two fasteners securing the drivers side taillight assembly. Next, pop it from its position, being careful not to break the alignment tabs underneath. Then we'll locate the wiring for the reverse taillight.

This will be the black and red wire running into the grey connector. Next we'll need to find which side is hot when the vehicle is put in reverse. With a piece of wire we'll go ahead and back pro the connector and use our test light with the vehicle in reverse, checking the connection point. As we can see, the test light goes off when connected to the red wire, so we'll know this is our hot wire when in reverse. It is necessary to be careful when putting it in reverse.

It is not necessary to start the vehicle but it will need to be in auxiliary mode with your foot on the break. It's a good idea to have an extra set of hands or feet to accomplish this task. To make our connection with the manufacturers wiring, we'll use the blue quick splice connector provided with our install kit, sliding it over the manufacturers red wire and then taking the blue wire and sliding it into the quick splice connector. We'll crimp it down and then close the clasp. Quick tech tip, I recommend to wrap up this connection point with some black electrical tape.

The we'll go ahead and start routing the wire. We'll feed the black connector end down between the bumper cover and the body or sheet metal of the vehicle, pulling it out underneath. Then to secure our wiring behind the taillight housing, we'll use more of the black zip ties provided with our install kit, cutting off the excess from the zip tie and then reinstalling the taillight housing. Next we'll go ahead and get underneath the vehicle and start routing our wire. To route our wires together we'll go ahead and cut the two zip ties holding the current four pole connector in place and then take the blue wire, route it through the hole in the hitch over to the four pole and route them together.

Next I'll take the adapter harness, plug it into the four pole and then the blue wire pigtail into the blue wire we just ran from the reverse taillight circuit. Quick tech tip, I recommend you use some dielectric grease in between these two connection points. We'll be using part number 11755. Now with the connections made, to clean up our install look and to protect this connection I'm also going to wrap it up with some black electrical tape. We're going to go ahead and route the wiring over to the center of the vehicle and out to the hitch. We'll use some black zip ties to secure our wiring behind the hitch to keep it safe and secure. With our wire secured we'll go ahead and use our side cutter to cut off the excess from the zip ties and clean up our install look. That will complete the installation of the Tow Ready adapter four pole to fie pole trailer wiring adapter, part number 20036 on our 2009 Nissan X-Terra.

Customer Satisfaction Score:

Customer Reviews

Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter - 20036

Average Customer Rating:  4.9 out of 5 stars   (249 Customer Reviews)

Trailer wiring adapter changes the 4 pole flat on your vehicle into a 5 pole flat.


Good quality and everything needed for install in my 2006 Honda Odyssey. Now I can easily tow with either a 4 wire or 5 wire since the harness retains both.


Adapter 4-pole To 5-pole Flat - works as described. Installed on 2013 Chrysler Town & Country. Connected blue wire to left rear light harness. Strongly recommend using a 12v tester for this install, as visual diagnosis can be wrong. Deduct one star because 5-plug has no cover and is susceptible to road grime. My solution is to leave original 4way plug with cover underneath the vehicle and connect 5plug adaptor only when towing boat.


Have a multimeter ready so you know which wire to splice on the reverse light. Glad this product exists!


E-trailer is one of the best online companies I have ever dealt with. I just make my second purchase on Sunday evening and had my hitch installed on my vehicle on Wednesday evening. The videos are very helpful. The communication back to me the customer is way above expectations...


This kit was easy to install and exactly what I needed. I had a particular need and reached out to eteailer and received a quick response. Perfect!


Simple install on my Jeep JK. Tapped the reverse light lead wire and harnessed all the wires in flex conduit. Tie strapped it all under bumper. Can either use 4 or 5 pin trailer.


Simple and easy to use; just plug it in and connect it to the trailer harness. Works like a charm!


Not installed yet but looks as good as one used before in a former vehicle. The actual adapter I received is "Reese", which is a reputable brand for towing accessories.


Great service. Wonderful (and numerous) how to videos are very easy to follow


My Ford Edge with the tow package had a 4 pole harness and my boat trailer had a 5 pole harness with the extra wire for locking out the brakes when reversing. This adapter was easy to install and works like a charm. No more need to use a lock out key when reversing the trailer.


Fast delivery! Works great with 5 pole flat connector on my Goldwing M/C and 4 pole on my truck


4 to 5 pin wiring plug is awesome bought the bracket that it fits in to secure to truck and it works very well was very secure until I backed into trailer hitch with it ..its still square and hold tight just need to rescrew it back on with bigger bolts and it will be good as new. I recommend this to everyone that needs 4 to 5 pin for there trailers its so easy to install takes 5 minutes.

Eldon W.


the product is still holding true to the truck and still preforms just as it was the day I installed it


This was exactly what I needed. Our Nissan Pathfinder came with a 4 prong plug already installed, but our new boat trailer has a 5 prong plug. This fit perfectly, works great (already used it this past weekend) and the installation was easy, thanks in part to the instructional video included on the product page. Would definitely recommend to anyone that needs to go from a 4 prong to 5 prong for your trailer.

Rich S.


Which wire did u crimp on to for your Pathfinder? Could u tell me the colour pls. Thanks.

Patrick B.


We've sent Chris an email to let him know about your question. Remember to always double check a wire with a circuit tester before connecting. Wire colors can change on the same model, even in the same year so the colors may not be the same. Just check before splicing.


My trailer has a five plug harness. The cord made it easy to convert from my wiring harness.


Had to rewire my 8' utility trailer. Purchased the wiring kit and couldn't be more pleased. Easy to install, clear instructions and fast shipping. THANKS!

Maj M.




Great product!


This is for a 2014 Jeep Cherokee Latitude. It took me a little extra time as my helper was a 5 ton floor jack and it supported the receiver and if only my right foot had fingers it would have helped a lot. Loading the bolts and plates into the frame was a snap, I left the fish wires on the bolts and that helped a lot and I didn't lose a bolt into the frame,you must leave the exhaust hanging to get to the rear bolt closest to the exhaust curve just before the mufflers I didn't and it was a bear to torque it. Also after I cut the opening on the bottom of the bumper and already had torqued the receiver I had to pry the bottom edge over the receiver there was no other way to get the hitch up inside not enough forward space to get it to slide up and in. Other than that it was a snap.
Now for the wiring harness, went well had a bit of a time getting the connectors up to the tail lights even with all 4 screws out and a little bit of play I had to pry the plastic support away from the body to get the connectors through. That was for the 4 flat, for the power for the harness I have a rig runner 4005 from Powerwerx for all my power as I am a volunteer Fire Fighter and have all the goodies that goes with it and every thing runs fine. For the 5 flat all I had to do was find and take out the backup bulb in the tail light and test to find which wire was hot. And then it was over and done put it all back together and drive away with my trailer. Sorry no picture it looks just like the factory/dealer put it on.
Ray H


As it turns out I really didn't need this part but it shipped fast and the customer service was the best I've encountered in a long while.


Works as advertised but the 5th (blue) wire provided is too short for my 2006 Honda Pilot. Not a big deal. You can buy 3 feet of 16 gauge wire at Ace Hardware (even in matching blue if you wish) and use butt connector or bullet plug to splice. Regarding which wire to tap into for the reverse lights: On my Honda Pilot, there are access ports to the reverse lights on the inside panel of the rear hatch. I just popped one of those covers out too see what color wire powers those reverse lights. (In my case, it was a green wire with silver spots and a very thin black line.) You can then tap into that wire at top of the hatch in the same manner shown in the video on eTrailer's website (for a Toyota Highlander if I recall correctly).


I have been using adapter #47515 to convert my 4 pole vehicle to my 5 pole trailer plug. The extra wire was necessary to operate the solenoid on my surge brake trailer. It worked ok, but because the wire came into the 5 pole plug at a right angle, the wire seemed vulnerable to bending and then breakage. This product has the extra wire coming straight out the back to alleviate the bending/breakage concern. So far it has met my expectations.


I used this part to convert the four-pole wiring in my 2014 Toyota Sienna Van (previously installed using parts) to a five-pole so I can pull a boat trailer with hydraulic "surge" brakes. Everything worked well, but I had to get an extra length of wire and a butt connector at an auto parts store for my Toyota Sienna. The most time consuming part of the process was finding the reverse light wire in the bundle of wires going to the tail lights. A test light with the ability to pierce a wire (sharp point) is required for this.


The adapter was fine. The video showing how to route the backup light wire to the harness was terrible. Routing a wire under the hatch seal caused a leak that went undetected for 3 months. Had to pull all the seats out several times, remove all the moldy carpet padding, scrub the car and carpet many times, replace the padding, put all the seats back and have the interior professionally detailed. A better method is to route the wire under the headliner down the side. Stay away from the hatch seal.


The install was extremely easy on my 2017 Jeep Wrangler. Just route the wire from the left backup light down to the trailer connector following the current wire bundle. I haven't tried it with the trailer but with the back up lights on there was voltage to the trailer connector, so it should work.

Super fast shipping also.


installed wiring but had hard time connecting to back up lights....

Roland B.


Been using the harness without any problems..


The hitch assembly kit was installed without any difficulty. I haven't connected to
my trailer yet, but don't anticipate any problems. I was very impressed with the
ordering and shipping notification by your etrailer. I would recommend this
company to anyone else. The prices were very competitive with other companies.
Lew H.

Show More Reviews

See what our Experts say about this Tow Ready Trailer Wiring

  • Can 4-Way Plug Into 5-Way and Still be Functional
    Yes, a 4-way can plug into a 5-way and the 4-way functions will all be fully functional. The reverse light circuit would be the only thing that wouldn't work since it's not connected.
    view full answer...
  • Troubleshooting Trailer Wiring Where All Lights are On All the Time
    Typically when this problem happens the issue is that the trailer wiring harness on the tow vehicle is shorted out and is sending power on all circuits at all times. On a newer truck I would not anticipate that being the case though and instead I would look at the wiring of the trailer. Most likely there is a short between the 12 volt accessory circuit and the running light or both stop/turn circuits.
    view full answer...
  • 4-Way to 5-Way Adapter Recommendation for 2015 Jeep Wrangler
    We have just what you need. The adapter part # 20036 is designed specifically for converting a 4-way to a 5-way like what you have. The extra pin and wire on the vehicle side allows you to tap the fifth circuit into wherever needed. I attached an install video for this for you to check out as well.
    view full answer...
  • Part Needed to Convert 4-Flat to 5-Flat on Vehicle
    A 4-way only powers the light signals so I don't see how it could activate the brakes. I recommend going from a 4-way to a 5-way on your tow vehicle with an adapter, the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036.
    view full answer...
  • 5-Way Adapter Recommendation for 2010 Toyota Highlander with 4-Way
    The correct adapter you need is the part # 20036. This adapter will plug into the 4-way on your vehicle and will give you a 5-way to run to your reverse lights so that you can activate the reverse lock out solenoid. The extra wire of the kit allows you to tap into the reverse light circuit to activate the fifth pin of the connector.
    view full answer...
  • Recommendation to Connect 4-Way on Honda Pilot with 5-Way on Boat Trailer
    I have the perfect solution for you. In order to connect to the 5-Way on your boat trailer, I recommend using the Tow Ready Trailer Wiring Adapter # 20036. This will plug right into the 4-Way already on your Honda Pilot and provide you with a 5-Way to use for the boat trailer. The additional blue wire from the adapter will then just need to be connected to the reverse light wire on the vehicle so that it can activate the reverse lockout on the trailer actuator. I have attached a short...
    view full answer...
  • Can 5-Way with 6 Wires be Ran to 5-Way with 5 Wires
    Yes, you can run both of your trailer's brown wires to the single brown wire of your new 5-way. Typically this is how most 5-ways are wired. Your old one was a wishbone style connector which means it has the two wires already for that circuit.
    view full answer...
    Image 1 for
  • 4-Way Flat to 5-Way Flat Adapter for Boat Trailer
    We do have an adapter to go from a 4-Way on a vehicle to a 5-Way on a trailer. You can use # 20036. The extra blue wire will get wired into the reverse light circuit on the vehicle. The 5th wire on a boat trailer 5-Way is usually for an electric reverse lockout. When the vehicle is placed in reverse it sends a signal back to a solenoid on the actuator and does not allow the brakes to engage. You might also check your ground wire to make sure you have a clean ground.
    view full answer...
  • Is there an Adapter to Connect a 5-Way Flat Trailer Connector to a 4-Way Flat Vehicle Connector
    There is an adapter that will work for you, part # 20036. It will require that you run an additional wire to the vehicle and connect it, but the connector is included. You will need to trace the 5th wire on the trailer, usually blue, and find out where it runs. Usually it is for reverse lights or trailer brakes. If it is for reverse lights, you will connect the new wire to the reverse light circuit on your vehicle as shown in the video I have linked below. If it runs to brakes on the...
    view full answer...
  • Recommended 4-Way To 5-Way Trailer Wiring Adapter For 2010 BMW X5
    The fifth pin on the 5-Way connector on your trailer will typically be used on surge couplers that have an electric lockout feature. The pin that matches the trailer's fifth pin on the vehicle side will need to be connected to the reverse light circuit on your X5 for this feature to be active. I recommend using the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter, part # 20036. This adapter includes an additional wire that would attach to the reverse light circuit on the vehicle. I...
    view full answer...
  • 4-Way to 5-Way Trailer Wiring Adapter for 2016 Ford Expedition
    All you need to convert your 4-way to a 5-way is the 4 to 5-way adapter part # 20036. This will plug right into your current 4-way and then gives you an additional wire you can run to the reverse light circuit of your vehicle to activate the pin.
    view full answer...
    Image 1 for
  • 4-Way to 5-Way Adapter Recommendation for Boat Trailer with Surge Brake
    You'd have to use a 4-way to 5-way adapter as you'd need a separate pin for the 5th circuit. If you tried to run it on another circuit you'd have issues on both circuits. So the correct adapter you'd need is the part # 20036. The fifth circuit would need to be ran to the reverse light circuit of your vehicle.
    view full answer...
    Image 1 for
  • Which Wire to Hook Tow Ready Trailer Wiring Adapter To 2007 Honda Odyssey Reverse Light
    On the Tow Ready Adapter 4 Pole to 5 Pole Trailer Wiring Adapter, # 20036, the blue wire gets tapped into the reverse light circuit, if your trailer has a surge brake coupler. If you have electric brakes or electric over hydraulic brakes you would attach the blue wire to the output wire from the brake controller. I am sending a video link of that part number being installed which might help you.
    view full answer...
  • Finding Backup Circuit Wire on 2016 Dodge Durango to Install Tow Ready Adapter # 20036
    Based on my research the backup circuit wire on your 2016 Dodge Durango is going to be a voilet color wire on the left side lamp or a light blue wire on the right side, although I do still recommend verifying this with a circuit tester. The backup lights are indeed on the liftgate of the Durango but the wiring does still extend further up the vehicle until it terminates at the body control module beneath the right side kick panel. You should be able to access the reverse circuit wiring...
    view full answer...
  • Recommended Adapter For 4-Way To 5-Way Trailer Connector
    To convert a 4-way to a 5-way, I recommend the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036. This adapter will give you the 5th wire connection to allow you to add that reverse function or brake function depending on your trailer setup.
    view full answer...
  • Why Does 5th Pin of 5-Way Adapter Run to Reverse Light on Tow Vehicle
    The fifth circuit of a 5-way is commonly used for the reverse lock out of a trailer with surge brakes. Since that is the most common use of the 5th circuit that's why it's recommended to be installed there. If you have a different need you can attach it to a different circuit.
    view full answer...
  • How to Convert a Vehicle 4-Way so that it Works with Trailer 5-Way
    You actually don't need any of those parts to connect the wiring from your tow vehicle to your trailer. We have the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036 which plugs into the 4-Way on your vehicle and has extra wire to tie into the reverse light function on your vehicle. This will activate the basic lighting functions on your trailer as well as the reverse signal. An example installation video has been linked for you to check out.
    view full answer...
  • 4-Way to 5-Way Adapter Recommendation for 2015 Ford Edge
    We have exactly what you are looking for. The 4-way to 5-way adapter part # 20036 will convert the 4-way to a 5-way and will allow you to run the additional wire to the reverse light circuit on your Edge so that it will activate the reverse lock out solenoid of your surge brake actuator.
    view full answer...
  • 4-Way to 5-Way Adapter Recommendation for Boat Trailer
    An extra red wire for trailer wiring is not commonly seen, but since you said this is a boat trailer it's most likely for a reverse lock out solenoid. Does the trailer have surge brakes? If so, this would be the case. This circuit would need to get run to the reverse light circuit of your tow vehicle so that the actuator can allow the trailer to be reversed. We have vehicle 4-way to 5-way adapters as part # 20036 but before we go down that route let's first be sure the red wire is the reverse...
    view full answer...
    Image 1 for
  • Recommended 4-Way To 5-Way Adapter For Boat Trailer
    To convert your 2008 Ford Ranger from a 4-way to a 5-way trailer connector, I recommend using the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036. That 5th function is typically for a reverse function and is used often times for the reverse lockout on boat trailers. You will want to attach the blue wire of this harness to the reverse light power wire on your tail light assembly. I've attached a video to assist. If your boat trailer has an electric lockout and you don't install...
    view full answer...
  • Towing a Trailer with a 5-Way Trailer Connector with a 2011 Jeep Wrangler that has a 4-Way Connector
    You need an adapter that goes from the 4-way trailer connector on the back of your 2011 Jeep Wrangler to a 5-way. We have # 20036 which will do just that. On one end is a 4-way connector that will plug into your Jeep's along with an extra wire that will need to be spliced into the reverse lights on the Jeep. Then on the other end will be a fully functioning 5-way connector once it's installed.
    view full answer...
  • Can a 2013 Kia Sorento Have a 5-Way Trailer Connector Installed
    The 4-way trailer connector on your 2013 Kia Sorento should have a powered converter which reduces the draw on the vehicle's lights. It draws the power for the trailer's lights directly from the battery. So you won't have any problems adding a 5-way connector. You can use an adapter like # 20036 that converts the 4-way to a 5-way. Your 4-way plugs right in and then the extra blue wire gets tapped into the reverse light circuit on your Sorento. If you don't already have a 4-way trailer...
    view full answer...
  • Does 4-Way Trailer Wiring Include Reverse Light Circuit
    4-Way trailer wiring does not carry the reverse light circuit. 4-way wiring carriers a ground, taillights, left turn/stop, and right turn/stop. Typically if the reverse light circuit is needed we recommend the 4-way to 5-way adapter part # 20036 which you could run to the reverse light circuit of the truck.
    view full answer...
  • Is Reverse Light Circuit Present on 7-Way to 5-Way Adapter
    As long as the reverse light circuit of your 7-way is active it will still be active when you convert it to a 5-way using your adapter without requiring any additional steps. You'd be able to tow the trailer with just a 4-way like you mentioned but to have the reverse light circuit active too you'd need a 5-way adapter like part # 20036.
    view full answer...

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