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20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground

20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground

Item # A20WB
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A20WB - Trailer End Connector Optronics Trailer Wiring
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4-Way trailer harness connects to your tow vehicle to control trailer light functions. Wishbone-style harness comes with 2 tail light wires split for simple wiring. Lowest Prices for the best trailer wiring from Optronics. 20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground part number A20WB can be ordered online at etrailer.com or call 1-800-496-5010 for expert service.
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Optronics Trailer Wiring - A20WB

  • Trailer Connectors
  • Trailer End Connector
  • 4 Flat
  • Plug and Lead
  • 11 - 20 Feet Long
  • Optronics

4-Way trailer harness connects to your tow vehicle to control trailer light functions. Wishbone-style harness comes with 2 tail light wires split for simple wiring.


Features:

  • 4-Way trailer harness connects to your tow vehicle to control trailer light functions
  • Wishbone-style harness comes with 2 tail light wires split for simple wiring
    • Allows you to run wires separately down each side of the trailer to tail lights without needing a jumper wire
  • Color coded wires help with installation
    • White - ground
    • Brown - tail lights
    • Yellow - driver side stop/turn
    • Green - passenger side stop/turn


Specs:

  • Wire harness length: 20'
  • Ground wire length: 30"
  • Wire gauge: 20 AWG


A20WB Optronics 20 ft. Wishbone 4-Way Trailer Wiring Harness with 30" Ground Wire




California residents: click here


Video of 20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground

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




Video Transcript for Optronics Wiring - Trailer Connectors - A20WB Review

Today we'll be reviewing part number A20WB. This is Optronics 20 foot wishbone 4-way trailer wiring harness with a 30 inch ground. It's going to feature a 4-way flat connector. Wires come straight from that and they immediately split all the way to the very end. Again, you're going to have 20 feet in total length. Then you're going to have that 30 inch ground wire.

This harness will work as an exact replacement for truck light number 108820. That's going to do it for our review of part number A20WB. This is Optronics 20 foot wishbone 4-way trailer wiring harness. .

Customer Satisfaction Score:


Customer Reviews

20 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - A20WB

Average Customer Rating:  4.9 out of 5 stars   (270 Customer Reviews)

4-Way trailer harness connects to your tow vehicle to control trailer light functions. Wishbone-style harness comes with 2 tail light wires split for simple wiring.

by:

worked out fine! MY NEW DOG SEEMS TO HAVE A TASTE FOR CHEWING UP EVERYTHING, INCLUDING THOSE TEMPTING LOW HANGING FRUITS ON ALL MY TRAILERS. UGH!




by:

Wishbone style is the way to go. Received harness today and installed this afternoon. I have ordered various items over time from etrailer and always satisfied.




by:

Some men, when they arrive at sixty five or above, run out and buy a fancy red sports car. I bought an old trailer that looked good and sturdy. It was very inexpensive. It needed some welding and rewiring. Luckily I have a neighbor who is an excellent welder, and the wiring was easy to find on the web and easy to install. I have gotten great pleasure using my trailer. I even thought about painting it red, but then that would look ridiculous.


Comments
Very good. Product has held up nicely
Jonathan - 05/26/2022


by:

Just wanted to let you know that the Optronics Miro-Flex Trailer Lights are working great!! Much brighter and more visible that the basic lights I replaced! Hope your business is doing well through this Covid crisis!! Thanks for the communication.


Comments
Outstanding
Michael I - 04/24/2022


by:

Rewired the lights on my old trash trailer. Only took an hour. The cable was perfect. I was impressed with the four way connector.




by:

Cheap--wired it in to my Chevy and tried to separate the male connector from the female and the rubber sleeve separated from the terminals on the make connector. Threw the GARBAGE into the garbage and re-installed my old one. Do not buy this cheap junk. Wish I would have taken a photo.




by:

It's a simple item but try to find it somewhere else as a stand alone product.
I've used etrailer before with great results and this was no exception. Let's be honest, if you've been to the site once, you're coming back!
I have a 5 x 12 utility trailer that has good lights but the wiring was a disaster. The harness connector had been patched and there were at least 5 splices throughout the lines. It was nice to lay out the new harness, make the light connections, tack everything up and out of harms way (there's an idea) and my lights work like new. I like the ground fastens under the jack bolt. Saves drilling a screw in (see the baby hole?) Good to feel safe on the road again. As easy and inexpensive as it was, I don't know why I waited so long.




by:

Item was a described, I wish they sold the plug with about 12 inches of wire, I did not need 20 feet




by:

After trying to spice wires with other kits I found ETRAILER made a order got in just a couple days and had it wired hassle free this is a great product and I even order another one for my boat trailer and a easy plug kit for my jeep!! Will continue to use ETRAILER in the future!!




by:

Glad I was able to find the right cable




by:

very good to have trailer parking light wires in a wishbone configuration




by:

Just what I needed and price great. Tha nks




by:

Just rewired a cargo trailer I bought that the lights were always going out. Found 20 butt connectors the guy used no wonder they worked off & on. Now with two new tail lights & new wiring with a straight connection everything works like it should. Everything I have bought from etrailer has been good quality & fast shipping.

Thanks




by:

Rewired the trailer relatively easily. Had a ground problem that was easily fixed. My only problem was the VERY long shipping. There is no excuse.


Comments
As advertised . Shipping was slow
William E - 07/23/2021


by:

Comes with two brown leads making it dead simple to install. Just lay it all out and install it. Seems to be of good quality too. Nice wire gauge.


Comments
That complete rewire is still working fine after a year. Very satisfied.
Bryan - 11/03/2021


by:

I have been very pleased with the quality of the product and that it is very durable and works great . The wire seems to be holding up well




by:

product worked great price was ok easy to follow directions




by:

Always get great products and service from etrailer




by:

Fantastic !!!! Great product, exactly as detailed, exactly as pictured, easy ordering, and on time shipment / arrival. I have never wired a trailer before, but after watching the online video program and following the steps I was able to complete the project in a hour for a 14' boat trailer. Prior to ordering, I did a lot of price comparisons in my area and I could not beat etrailer pricing. Great product.


Comments
Thanks for the follow up - One year later the products are working spectacular and I keep plugging away at your company - telling all of my friends about it.
Martin F - 10/19/2015


by:

This harness worked great for installing tail/brake lights on the back of my bike rack.




by:

Excellent service as always and great prices on quality parts




by:

Harness was purchased to rewire my Shoreland'r boat trailer. It came very well
packaged. The internal wire was strong and did not fray when stripping off the sheath. The main thing I liked was that the right and left (gr/br & yel/br) wires were separated all the way to the connector. The shipping fees were very reasonable. I would recommend this product all day. THANKS etrailer.com. Now if I could just figure out why I keep blowing my running lite fuse in my truck???


Comments
First you want to make sure your ground wires on your vehicle wiring and your trailer wiring are attached to bare corrosion free metal. If your grounds are properly attached, It sounds like you have a short circuit somewhere. You need to determine where the short is. To determine where the short is you need to test the vehicle side wiring and the trailer side wiring with a 12v probe-style circuit tester. I have attached a link below to help you.
-- Etrailer Expert Heather A - 09/26/2017


by:

What do y'all want a follow up to? If i had a nickel for every item I've ordered off of ETrailer, I wouldn't have to work for a few months... I keep coming back because the prices are fair, shipping is free and fast, and ETrailer has everything I need.

I do wish you sold trailer kits though. Being a welder, I have built a few trailers in my free time and sold them for a small side business. Why isn't there an axle, fender, brakes, springs (shackles and all hardware) tires and wheels kit? It would be nice to not have to go and click and add to cart all the multitude of items I need to build a trailer individually. Just saying...




by:

The wiring harness was just as I had hoped.

I had ordered one earlier from another supplier and the quality was so poor it was unusable.


Comments
The wiring harness is still fully functional as expected
Craig H - 05/08/2018


by:

Overall the wiring harness was satisfactory. Would recommend adding more length to the ground wire. In addition, addition of several splicing connectors (to run wires to the side lights and connect the tail lights) would be beneficial. Finally, a dust cap for the four prong connector would be an improvement. All that being said, the product installed quite easily.



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Show More Reviews

See what our Experts say about this Optronics Trailer Wiring

  • Trailer Lights Stop Working When Headlights are Turned On with a 2007 Chevrolet Avalanche
    The most likely cause of your problem is a bad ground connection. It has enough of a connection that it works in the day time because you have less current draw on those circuits with the head lights off. As soon as the headlights are on, you are pulling more current than the weak ground can support. Check the ground connections on the trailer wiring. Make sure you have good metal to metal contact. Paint and corrosion can act as insulators so make sure the grounds are touching clean metal....
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  • What Gauge Wire is Used in the Wishbone 4-Way Trailer Wiring Harness, # A20WB
    I spoke with my contact at Optronics about the Wishbone 4-Way Trailer Wiring Harness, # A20WB. They had documentation stating the green wire is 19 gauge and the yellow wire is 20 gauge. She could not state for sure what gauge the white and brown wires are but either 19 or 20.
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  • Troubleshooting Trailer Lights That Stopped Working After Bulb Replacement
    There is no difference between the red and amber colored trailer lights. They are the same lights with a different color lens on them. If all of the lights on your trailer went out I would suspect you blew a fuse somehow in the process of replacing the light. I would check the fuse box of the vehicle you connected this trailer to looking for the trailer wiring fuses and replace as necessary. I attached an FAQ on trailer wiring as well as troubleshooting 4-way installs that should be helpful...
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  • Wire Gauge for the Wishbone 4-Way Trailer Wiring Harness, # A20WB
    I spoke with my contact at Optronics about the Wishbone 4-Way Trailer Wiring Harness, # A20WB. They had documentation stating the green wire is 19 gauge and the yellow wire is 20 gauge. She could not state for sure what gauge the white and brown wires are but either 19 or 20.
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  • No Brake Lights or Turn Signals on Trailer With a 4-Way Connector With 5 Wires
    You will first want to make sure the 5 wires on the trailer plug is wired properly to the trailer. The white wire is for ground, the green wire for right turn and brake, yellow wire for left turn and brake, green with brown wire is for right side running lights, yellow with brown wire is for left side running lights. If the wiring is all correct then you will need to check the trailer connector on the truck and trailer for a ground connection issue, or a short on the tail light circuit...
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  • Should Boat Trailer Lights Short Out When Backed Into Water
    Water and electricity don't mix well. The best recommendation I can make for you would be to unplug your trailer wiring before you back your boat trailer down the ramp and then don't plug the lights back in until the trailer has dried out thoroughly. While the trailer lights themselves can be listed as waterproof or submergible the wiring of the trailer isn't always so that is why unplugging the trailer lights is recommended. If the assemblies were ever replaced water can easily get in...
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  • Replacement Wishbone 4-Way Recommendation for a Trailer
    You are correct. Based on the wire colors that you listed you would want a wishbone 4-way like the part # A20WB. The colors of this 4-way would match up exactly to what you have listed with the only addition being the white wire of the new 4-way running to a clean metal surface on your trailer. The brown wires of the 4-way will be run to the yellow/brown and the green/brown wires. It doesn't matter which one as it's the same circuit (running lights). I attached an install video for...
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  • Trailer Lights Function Differently on Two Different Vehicles
    If you have different lighting issues with the trailer depending on which vehicle you are using then that leads me to believe there is an issue on the vehicle. I recommend you check the trailer lighting circuit fuses on each tow vehicle to make sure all is in order. Also, I recommend you run a ground jumper wire for each light up to the main trailer connector ground as well temporarily to see if that fixes your issue. If you want to check the trailer on its own then you can do so with the...
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  • Wire Color for Each Function on 4-Way Trailer Wiring
    You likely saw it on our wiring help article which I linked. The traditional wire coloring of a standard 4-way like # A20WB is both browns to your running lights, one per side of the trailer, green to your right turn and brake light, yellow to the left turn and brake light, and the white is the ground wire.
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  • Will 20 ft. Wishbone 4-Way Trailer Wiring Harness # A20WB work with LED Trailer Taillights
    Yes, the 20 ft. 4-Way plus Wiring part # A20WB that you referenced will work great with LED trailer lights. There's no reason that it wouldn't work. This is a wishbone wiring kit for the running light circuit which means that the running light circuit has a wire for each side of the trailer. That's why there are two brown wires. I attached an install video for this kit for you to check out as well.
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  • How Does Wishbone 4-Way Wire to Trailer's 4-Way Wiring that has 7 Wires
    The two white wires are the ground circuit which would run to the white wire of the # A20WB, the black wire has to be the right turn/stop signal although that color is typically solid green. The brown is a running light circuit that runs to clearance lights on the trailer, the yellow brown runs to the taillight assembly for the running light circuit, and green brown is the left turn/stop circuit. All of these run to either of the brown wires of the 4-way, and then the yellow is the left...
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  • Wire Gauge and Ground Locations for LED Running Lights on a Trailer
    Since LED lights do not require a lot of amperage you can go with relatively small wire. Using 16 or 18 gauge wire will be fine. Harness # A20WB uses 20 gauge wire which is on the small side but certainly not a problem at all for LED lights even incandescent lights on a trailer. We have various types of 16 and 18 gauge wires, see links, depending on the configuration needed. Also many of the options are sold by the foot so you would change the quantity amount to reflect how many feet you...
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  • Can 4-Way With 5 Wires be Used as Replacement for Standard 4-Way
    The spare 4-way you have is called a wishbone harness, such as the Optronics # A20WB which can be used as a replacement for your current plug. You will notice the two yellow wires you were referring to connecting to a single pin on your connector. The two yellow wires will likely be for the left side and right side running lights so you can connect those wires to those circuits on either side of your trailer, meaning you won't have an "extra" wire. I have also added a link to a help article...
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  • Troubleshooting Trailer Stop/Turn Circuit Not Active for 2011 Jeep Grand Cherokee
    It should be a fuse that is called trailer wiring right stop/turn circuit in the fuse box. It could also be cut wire up stream of the connector as well. I pulled up the owners manual for your 2011 Jeep Grand Cherokee and the only trailer towing fuse listed is in the J14 lamps and it looks like it covers all the circuits. That makes me think that your problem is actually on the wiring of the connector and not on the vehicle.
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  • Recommended 4 Flat Wishbone Harness for Trailer
    The shortest 4-Way wishbone harness we currently have available is the 20 foot Optronics Wishbone 4-Way Trailer Wiring Harness # A20WB. This is a split wishbone 4-way trailer wiring harness that features the two brown tail light wires that you referenced. All the wires are 20-AWG gauge. Since the harness is a bit longer than you are needing, I recommend simply taping up any excess wire once the connector is installed. I have attached a couple short video demonstrations on this harness...
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  • Recommended 6 Foot Long Wishbone Wiring Harness for Boat Trailer
    The shortest wishbone 4-Way trailer wiring harness we have available is the Optronics Wishbone Harness # A20WB. This wishbone harness, which has the 4-flat connector with 5 wires, features 20 feet of wiring length. Since this is a bit longer than what you are needing, you can simply tie off any excess once you have everything installed. All the wires are 20-AWG gauge. I have also attached a couple video demonstrations on this product that you can check out.
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  • What is the Wire Material Made of on the
    I went out to our warehouse and pulled the wiring harness. The wire in the Optronics Wishbone 4-way Trailer Harness, # A20WB, is copper.
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  • How to Wire Up New 4-Way to Trailer When Wire Color Functions are Unknown
    It's interesting that your trailer connector has two green wires but aside from that standard wire colors. Typically white is ground, brown is running lights (where you would normally see 2 wires of same color), yellow is left turn/stop, and green is right turn/stop. You might try putting 12 volts via a car battery on both of the green wires to see what they illuminate. You may even try this for all of the color wires minus the white to make sure you have the functions determined. For...
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  • What Color Are the Brake Lights On A 4-Way Flat Plug Of Wishbone Wiring Harness?
    The brake signal is run along with the blinker on separate wires. The passenger side is normally green and carries the right turn and brake light. The driver's side is normally yellow and carries the left turn signal and brake. The remaining functions are running/tail lights on the brown wire and the ground which is the white wire. I've attached an article to assist. A wishbone harness like # A20WB will give you two brown wires so you don't need to run a jump wire from one side of...
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  • Can 4-Way with 4 Wires be Used with 4-Way with 5 Wires
    Yes, the 4-ways with 4 wires and the ones with 5 wire perform the exact same functions so they both can easily be used together. What you have a picture of is a wishbone 4-way that has the two running light circuits on it. One for either side of the trailer. That's why it has 5 wires. The 4-wire 4-ways use a single wire for this circuit but you then have to split it off to either side of the trailer. The two wires in your picture that have brown on them are that circuit. # A20WB is an...
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    Image 1 for
  • Does Optronics A20WB Trailer Wiring Harness Use All-Copper Wire
    The Optronics 20 foot 4-way trailer wiring harness, part # A20WB is constructed of 18 gauge stranded all-copper wire. I've confirmed this with my Optronics representative.
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  • Why Would Trailer Wiring have Two White and Brown Wires
    It's not uncommon for trailer wiring to have more than one wire for the same circuit for the ground and running light circuit. For the running light circuit (brown wire) this is to allow you an easier way to run the circuit to either side of the trailer. For the ground circuit (white wire) it's to allow for making more ground circuit connections easier since all of the circuits have to be grounded. So if your trailer has two ground wires you could run them both together and then to the...
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  • 4-way Wiring Recommendation for a Wishbone Wired Boat Trailer
    What you have is a wishbone 4-way that seems to have a few circuits run to the ground circuit (the jacketed circuit that has the 2 white wires plus the green wire with the white tracer). What you could use would be a 20 ft. Wishbone 4-Way Trailer Wiring Harness # A20WB. This has the wishboned running light circuit. Aside from that you would need to run all the wires to the ground circuit of the # A20WB. Basically you will need to run the wires all together from each circuit of your boat...
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    Image 1 for
  • What are the Wire Functions on 4-Way Trailer Side Connector 18004
    On the Draw-Tite 4-Way flat trailer side connector # 18004, the white wire is ground, brown is running lights, yellow is left turn signal/brake lights, and green is right turn signal/brake lights. Some trailers have what is called a wishbone harness, such as # A20WB. These harnesses will have 2 running light wires, one for each side of the trailer. This is so you do not have to run a jumper wire from one side of the trailer to the other to get running lights on both sides.
    view full answer...


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