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Wiring > Trailer Connectors > Trailer End Connector > 4 Flat > Plug and Lead > 35 Feet Long > Optronics


35 ft. Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire

Optronics Wiring

ratingratingratingratingrating (83 reviews)


Code:   A35W42B

Retail:$14.95

Price:$12.95


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Optronics Wiring - A35W42B

35' Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire

This is a 35' split wishbone 4-way trailer wiring harness with four conductors and a 42" ground wire.

  • 4-pole trailer end connector built-in
  • 35' long harness
    • 42" long ground wire
  • Each wire is 20 gauge
  • Y harness contains an extra tail light wire
    • Makes wiring a trailer quick and easy

Because the brake signal is sent along the same wire as each turn signal, the tail light signal is the only one that needs to be run along both sides of a trailer. The y-harness with 4-pole connector contains 2 separate tail light wires (brown wires), one bundled with the left turn and brake wire (yellow wire) and one bundled with the right turn and brake wire (green wire). It's the most efficient way to wire your trailer.

Manufacturer Cross Reference
Harness will work as an exact replacement for:
Truck Lite # 108835





Video of 35 ft. Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire


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

Video review of trailer wiring
Trailer Wiring and Light Replacement Demonstration
Video install optronics wishbone trailer wiring harness a35w42b
Trailer Wiring Harness Installation

Video Transcript for Trailer Wiring and Light Replacement Demonstration

Today were going to be replacing the wiring on this trailer. We will be replacing a 4 pole flat, as you can tell this one is pretty beat up and worn, so it has to be replaced. We are going to cut this wire off and we are going to replace this brown wire also. We are going to cut this loose and pull the rest of our wire through, on this trailer here it is pretty open so we can reach the wiring. Just in case though, if your wiring was run in conduit and you are replacing it, do not pull all of this out yet. We will actually tie on the new wires and use these wires to pull them through. We are going to cut off all of this old wire here, and we are going to take off this old light too. I would like to point something out on this 4 pole flat, you will notice there are actually 5 wires coming out of it. What is happening is on the inside of this pin, which is for the running lights, has two wires coming out.

The reason for that is we can split the running light circuit to both sides of the trailer. Mainly that is used on boat trailers and other light duty ones. What is nice about that if you have a running light on the side, chances are your running wire right next to it. You can tap into your wiring without having to make a wire go all the way across. It basically provides a short cut. This case we are going to run it all the way on one side and jump over since we have a small trailer and no running lights. Now we are going to tape our new wires to the old ones and pull it through the frame. It does not take much, just enough to make it smooth so it does not snag anywhere. Now we simply pull the wire through. Before we pull everything through, we are going to make sure we have enough leader to hang out. This unit comes with a pre-wired ground wire so we are going to leave it at its maximum length and this is where we are going to ground it at and well have a good idea of how much slack we need to leave. At this point its a good idea to tape up all the wires together that way it will keep them from getting tangled with anything else. Since we have our ground here we are going to ground it but before that we are going to take this loop off for a smaller one. Since we have an existing ground that works pretty good, we will use a smaller screw. Always give it a twist when you crimp it down it will make a nice tight fit. We will re-install our screw but first we will put a pit of dielectric grease on there to help protect it a little bit, electricity still flows on the ground and the less rust the better. Now we can pull the rest of our slack out.

We have our lights pulled over to the left hand side, we are using the yellow and the brown, yellow for left turn. We need to cut this wire to length about 1/2 to 3/8 inch. The wires then get stuck inside here there is a little strip in here that pulls against it and when you pull it back it catches so it can not come out and makes electrical contact. You bottom out the plastic and give it a little bit of a pull back and it catches. Same thing with the left turn signal. If you notice there is two holes side by side here. You could actually jump another wire from this hole here to another light, so it acts like a miniature junction box. This little channel here hides the wire so when you push it up against your frame it wont get mashed. Your light gets installed just like that. Before we bolt on our light we are going to clean this area out where the holes are that way it makes a good metal to metal contact with no rust and corrosion. You can use a file or scrape it if you are in a hurry but if you can use something more abrasive. You do not have to get these super tight, just snug them down and they will be fine. Again were going to use the old wire to pull the new wire through. Now were back on the right side of the trailer and we will do the same thing, we will run the wires and install a new light. Now we will install our wiring, green for the right turn and brown for the running light. One more final touch will be to run some loom clamps to the wire to keep it up closest to the bed. It does not touch anything, but it is better to keep it out of the way. At this point we will reassemble our trailer and test out the lighting. We have our trailer wired up, lets give it a test run. Notice we did not connect our truck to the trailer so we can make sure our ground wire is working. It is not a good idea to ground through the ball because it can be intermittent from bouncing around going down the road. First we will test the running lights then the turn signals, then the brake lights. We will do this for both sides. There you have it for our install of our trailer wiring harness. We used part number A35W42B and the tail lights we used, the left hand side was part number 432400 and the right hand side was 432200.


Customer Reviews

35 ft. Wishbone 4-Way Trailer Wiring Harness with 42 - A35W42B

Average Customer Rating:  ratingratingratingratingrating4.9 out of 5 stars   (83 Customer Reviews)




- A35W42B

ratingratingratingratingrating by: Joel T.03/23/2014

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This item would be perfect if the ground wire ran to each tail light with the rest of the wiring and it came with a schematic, but for less than $20, I'm still extremely impressed. No more phantom intermittent trailer light issues.121850



- A35W42B

ratingratingratingratingrating by: Dan10/28/2013

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I looked around for this product locally and on the web got quite some time before finding it here on etrailer. This connector comes in so many configurations it's easy to buy the wrong one. The description was enough to give me confidence. Package came swiftly, even though shipping cost as much as the item, but that's not etrailer's fault. Will shop here again.105406



- A35W42B

ratingratingratingratingrating by: Bob R06/29/2013

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I had a hard time finding a harness locally that would fit my trailer which is 28' plus 3 ' to vehicle. the 42' ground wire is a plus. The wiring information that the site provides is a big plus min trouble shooting problems. Will buy again from etrailer86754



- A35W42B

ratingratingratingratingrating by: Ray R05/20/2013

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I received 2 of these wiring harnesses and wired my utility trailer and boat trailer in less than 2 hours after receiving them. The video was very helpful great product. I will be using etrailer from now on. Thanks folks!81088



- A35W42B

ratingratingratingratingrating by: Eric C.05/10/2013

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This harness made for a seamless installation. I simply tied some string to the ends of my old wiring, pulled it out, and pulled this one back in. Then crimped some connectors on the end and plugged in my lights. My whole trailer re-wire took about 1 hour. This product has the wires bonded together (Grn/Brn & Yel/Brn) for quick and easy installation!79738



- A35W42B

ratingratingratingratingrating by: Glen S.04/08/2013

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It looks like just what I wanted, and it will work beautifully, but I have decided to up grade the lights to LED's, because the old 1157s would go out every time I hit a pump in the road, so I have another order to you for those LED lights.74843



- A35W42B

ratingratingratingratingrating by: Matt11/06/2012

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Should have bought it when I got new taillights,wa too much time on old wiring issues.Lifted my trailer up on it's side with my tractor and was done in 1/2 hour.Live and Learn. A couple of quick splice connectors for side lights would make it better than excellent.58911



- A35W42B

ratingratingratingratingrating by: Rich P.10/19/2012

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4 pole 35 foot trailer wire harness. This is a great product. 35 feet is hard to find at marina's. The 25 foot is quite common but is too short for my trailer. Even on line this is the only 35 foot that I found and it did not cost any more than the 25 foot at other web sites.57688



- A35W42B

ratingratingratingratingrating by: DougP09/20/2012

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Nice wiring kit for a 6-12 foot utility trailer. The only thing missing was the instructions, which were on the website / U-Tube as a video with a written transcript. The only thing that would have made it better would be to include accessories like clips, tap splice connectors or wire nuts. Eventually, also purchased a channel light kit, and running lights. the light kit came with the accessories mentioned and a 25' version, but the wires in that set were not as nice as these. This was a good purchase for my application.55338



- A35W42B

ratingratingratingratingrating by: Jim W.06/13/2011

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The product is fine and will do the job as required. As a novice, I was disappointed not to have some sort of diagram included with the item. A quick Google search gave me what I needed, but I think it should have been included, maybe with some helpful installation tips. The length was greater than I needed, but I coiled the wire in a couple of areas in case I need to make new light connections in the future. This way the wire is there and I won't have to splice in new wires. I'll have to see how the quality holds up over the next couple of years of salt water launches. Price was much better than Lowe's. 16844



- A35W42B

ratingratingratingratingrating by: Mike W.05/27/2011

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I had purchased a replacement harness for my 21 foot boat trailer before looking closely at how the manufacturer had rigged the wiring for the lights. Unfortunately, the running light circuit was run down the left side and wrapped around the rear to the right side making that run over 30 feet and making that harness unusable. The right side did not have retainers (welded to the frame as did the left) to run a true wishbone harness on both sides from the front. This 35 foot harness (though a wishbone) works perfectly to re-rig the lighting as it was originally. No adapting or modifying necessary. 15564



- A35W42B

ratingratingratingratingrating by: Glen L.12/16/2010

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Customer Service This is my second purchase with etrailer.com. My first was a factory wiring harness for my Ford Escape. Perfect fit and the included directions were right on. I now need to replace the plug on my trailer and it is a 4 prong but has 5 wires which none of the local stores had. Back to etrailer.com where I identified a matching kit with ease. They responded to my orders the same day I placed them and shipped next day with plenty of correspondence during the purchases. The products and service are top knotch. I highly recommend them, you won't be diappointed. Sincerely, Glen Lang4218



- A35W42B

ratingratingratingratingrating by: Jim Mc12/15/2010

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Trailer harness kit Katie, thanks for letting me know the package was delivered and sitting outside my garage door! Your shipping and tracking service is the best I've experienced on internet ordered items. And the kit length enabled me to overcome a few personal errors in repair, with excess wiring left over. Thank you for a good product and great service.4173



- A35W42B

ratingratingratingratingrating by: JIM P.08/08/2013

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I BOUGHT A USED TRAILER AND THE LIGHTS DIDN'T WORK. I FOUND OUT THAT MICE HAD CHEWED THE WIRING THAT RUNS THROUGH THE TUNG. THIS PRODUCT WAS A GOOD REPAIR SOLUTOIN. IT ONLY HAS A 42" GROUND WIRE. SO I HAD TO ADD SOME GROUND WIRE BECAUSE MY TRAILER RUNS THE GROUND WIRE ALL THE WAY TO THE LIGHTS INSTEAD OF RELIAING ON TRAILER FRAIM GROUND.93919



- A35W42B

ratingratingratingratingrating by: Jim R.04/14/2014

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Product was quickly delivered and worked great.124972



- A35W42B

ratingratingratingratingrating by: Grady02/10/2014

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Have not installed yet, but it looks like exactly what I needed.116178



- A35W42B

ratingratingratingratingrating by: cfl0217712/04/2013

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plenty of length to work with and price-shipping were very reasonable. watching available videos regarding trailer wiring and lights was informative and prompted purchase.109077



- A35W42B

ratingratingratingratingrating by: Steve B12/02/2013

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These guys have been great to do business with. The product I ordered was as described, and the quality is what I expected. Delivery was prompt as well. I will be a returning customer.108786



- A35W42B

ratingratingratingratingrating by: Pete E.11/24/2013

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Good quality product. Product shipped same day as ordered and arrived promptly. Great communication from etrailer concerning order status. Great how-to videos.108314



- A35W42B

ratingratingratingratingrating by: Bob T.10/21/2013

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Needed to change out the wiring on my boat trailer....worked great!104587



- A35W42B

ratingratingratingratingrating by: Chris D.10/12/2013

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This harness was perfect for rewiring my cargo trailer. Having two running light (brown) leads is great to run down both sides of the trailer for clearance and tail lights. 103616



- A35W42B

ratingratingratingratingrating by: Janet K.10/10/2013

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This is what we needed. We frequently have to change out our wiring systems. This fit perfectly.103401



- A35W42B

ratingratingratingratingrating by: Robert R10/10/2013

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Got the wires yesterday and put them in my trailer today. Easy to install and lights work great. And had plenty of wire left over.103286



- A35W42B

ratingratingratingratingrating by: Brian k10/03/2013

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Great service, great product an well made! Makes hooking up running lights an LT/ RT turn easy without running wires across the trailer, definitely a benefit. 102443



- A35W42B

ratingratingratingratingrating by: Mike M.09/27/2013

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Item is as described, priced fair, and prompt shipping. A printed installation wiring diagram would be helpful. It is available online, however it would save time to include one in the box.101820



- A35W42B

ratingratingratingratingrating by: L. Johnson09/09/2013

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Intstallation was easy and extra tail light wire made quick work of re-wireing my trailer. Thanks etrailer for quikly shipping this product.99030



- A35W42B

ratingratingratingratingrating by: Patrick08/27/2013

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Product worked well and was easy to ins tall97270



- A35W42B

ratingratingratingratingrating by: Tony Mauro08/27/2013

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This is a good product and the second time I'm using it. My trailer gets a lot of use and the wiring gets beat up on a regular basis. It nice that the wiring comes split into a left and right side. 97135


Comments

The wiring split certainly makes the project faster and easier. You might want to check out some wire loom. It will add harder plastic jacket to the wiring and hopefully dramatically increase the time in between re-wire jobs.

Patrick B - 8/27/2013

1977


- A35W42B

ratingratingratingratingrating by: Ramone08/23/2013

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Fast shipping great service! 96652



- A35W42B

ratingratingratingratingrating by: John C08/21/2013

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Nice quality, exactly what I needed. Delivered in less than a week cheaper than I could have bought locally. 96302



- A35W42B

ratingratingratingratingrating by: Tom T08/15/2013

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Great for the price. 95230



- A35W42B

ratingratingratingratingrating by: Derek P.08/14/2013

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Very easy to install and use, not to mention good service and fast shipping95019



- A35W42B

ratingratingratingratingrating by: Adam M.08/13/2013

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Product worked perfectly and the two separate brown wires made the job even easier. The install took less than an hour.94787



- A35W42B

ratingratingratingratingrating by: Rod Pugh08/12/2013

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Awesome 94735



- A35W42B

ratingratingratingratingrating by: Mike M08/06/2013

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This was long enough to do the job of adding a light connection on the rear of a 29 foot travel trailer to pull my smoker behind it.93661



- A35W42B

ratingratingratingratingrating by: David08/06/2013

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Just what I needed. Installed in 20 min utes 93603



- A35W42B

ratingratingratingratingrating by: Rich Mc06/28/2013

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As described, worked great 86530



- A35W42B

ratingratingratingratingrating by: Chris F.06/12/2013

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Just the right thing for re-wiring my t railer.84365



- A35W42B

ratingratingratingratingrating by: Bill P06/07/2013

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Good product fast shipping 83778



- A35W42B

ratingratingratingratingrating by: Brett S.05/25/2013

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Exactly as described, thank you! 81946



- A35W42B

ratingratingratingratingrating by: Chris D.05/02/2013

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Nice to have this length available to help in eliminating splices. 78629



- A35W42B

ratingratingratingratingrating by: Mike Klassen04/25/2013

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I am very satisfied with the product, and the price was very reasonable. I would use this site again for my trailer needs. Thanks!!77775



- A35W42B

ratingratingratingratingrating by: george03/28/2013

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Very good quality. 73036



- A35W42B

ratingratingratingratingrating by: dan03/12/2013

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Got my order in 2 days. Product was exactly as expected. Will use this site again.70288



- A35W42B

ratingratingratingratingrating by: Dale03/05/2013

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I placed my order on a Tuesday and received it on Thursday. Item was exactly as described. I will definitely order from this company again. 68984



- A35W42B

ratingratingratingratingrating by: Melba03/05/2013

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Got what was needed at a great price without having to shop around and waste gas.68937



- A35W42B

ratingratingratingratingrating by: Dan K02/15/2013

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Hard to find 35 ft trailer wire kit. Needed something longer for guide posts lights. Customer service was awesome - kept me informed every step of the way. Arrived timely and ready to be installed66508



- A35W42B

ratingratingratingratingrating by: Michael01/28/2013

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The wiring harness was perfect but what I was most impressed with was the follow up emails on the shipping arrival and how quick I had received the part.....GREAT JOB!!!64358



- A35W42B

ratingratingratingratingrating by: Dan O01/14/2013

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Nice, easy to install wiring harness. Quality made with good sized wires. Worked great. The extra 10 feet more than other products allowed me to install it without splices.63039



- A35W42B

ratingratingratingratingrating by: victor01/11/2013

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Good quality and fast service 62759



- A35W42B

ratingratingratingratingrating by: nick s01/02/2013

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nothing like new wiring great quick and easy62371



- A35W42B

ratingratingratingratingrating by: Doug O11/28/2012

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Much better quality than I purchased lo cally.60083



- A35W42B

ratingratingratingratingrating by: Pat G11/13/2012

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As ordered, ready to install! 59340



- A35W42B

ratingratingratingratingrating by: John11/12/2012

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I was so happy to work with etrailer!!!! They (John the sales rep.) were VERY helpful and patient with me. I received everything and my trailer lights up and looks awesome with the new LED lights!59266



- A35W42B

ratingratingratingratingrating by: Mike Z.11/01/2012

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I really like the videos you have for your product! keep up the good work!58584



- A35W42B

ratingratingratingratingrating by: Kim Trevillian10/23/2012

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I have needed to rewire my snowmobile trailer for a while now. Now I can have trailer lights that work ALL the time! Thank You57944



- A35W42B

ratingratingratingratingrating by: SHH - Virginia10/08/2012

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Hard to find wiring harness length beyond 25' at most online retailers. Thanks etrailer.com. Easy transaction and prompt delivery.56723



- A35W42B

ratingratingratingratingrating by: KP09/04/2012

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I had a short in the wiring on my boat trailer and instead of trying to track it down I decided to just replace the wiring completely. This was more than enough wire for my 18' SeaRay trailer. The extra long ground pigtail is very convenient.53911



- A35W42B

ratingratingratingratingrating by: Brad L.08/28/2012

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This is exactly what I was looking for, but couldn't find at automotive stores. Unbelievably fast shipping! I ordered it on Monday, it arrived on Tuesday!!53345



- A35W42B

ratingratingratingratingrating by: joe08/09/2012

Is this review helpful?


E-100 bumper hitch fit perfect. It seems to be a pretty substantial hitch. I have not tow with it yet but it should work fine. I have not worked with the wiring are connections yet but they seem like they will work just fine. 51192



- A35W42B

ratingratingratingratingrating by: John Y.07/14/2012

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Great product for my home-built camper trailer. I was able to feed all the lights without splicing extra wire in. Fast shipping too! This harness saved me time and money and works great.47978



- A35W42B

ratingratingratingratingrating by: p kline07/10/2012

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Good wire 47416



- A35W42B

ratingratingratingratingrating by: Phil H.05/28/2012

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Easy to use 41847



- A35W42B

ratingratingratingratingrating by: bryce jernigan05/13/2012

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good quality 40266



- A35W42B

ratingratingratingratingrating by: Jon W.05/04/2012

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You won't find this product for a better price. Worked perfectly as described.39361



- A35W42B

ratingratingratingratingrating by: Bill T.03/30/2012

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Order for wiring, round plug, and plug mounting bracket delivered very quickly and is exactly what I needed. Have bought from etrailer.com in the past and always been well satisfied with their products and service.35648



- A35W42B

ratingratingratingratingrating by: JMO03/12/2012

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Just what I wanted......right price and shipped quickly.33593



- A35W42B

ratingratingratingratingrating by: straker03/05/2012

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all good. Good instructions, youtube films with installation guides and prompt delivery. Good product range as well33128



- A35W42B

ratingratingratingratingrating by: Phil B02/23/2012

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Great item just what i was needing and shipped sooner then was told.32258



- A35W42B

ratingratingratingratingrating by: Dale D.02/05/2012

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Takes all the guesswork out of trailer rewiring31122



- A35W42B

ratingratingratingratingrating by: Greg M.12/14/2011

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Excellent Quality Products. Just the parts I needed to do the job, Done right the first-time.28115



- A35W42B

ratingratingratingratingrating by: Jd11/21/2011

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Very nice product 27283



- A35W42B

ratingratingratingratingrating by: Curtis S09/01/2011

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Can't wait to use this on my trailer...typical wiring that you would expect for a trailer application. Sturdy connections from the wires to the plug.23372



- A35W42B

ratingratingratingratingrating by: JIm L08/23/2011

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such great service...great pricing...great products!!22559



- A35W42B

ratingratingratingratingrating by: Ps08/19/2011

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What I wanted 22121



- A35W42B

ratingratingratingratingrating by: Rick08/01/2011

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Product as listed - good price - quick shipping20679



- A35W42B

ratingratingratingratingrating by: Jim C05/13/2011

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I received the wiring harness in soon after ordering it and it was what we needed to rewire our trailer. I was quite pleased. The length allowed for rewiring clearance lights and tail/brake lights, ;lus providing a good ground.13795



- A35W42B

ratingratingratingratingrating by: Jim C05/13/2011

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I received the wiring harness in soon after ordering it and it was what we needed to rewire our trailer. I was quite pleased. The length allowed for rewiring clearance lights and tail/brake lights, ;lus providing a good ground.13794



- A35W42B

ratingratingratingratingrating by: Mike C05/03/2011

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I bought this wiring harness to re-wire my 28' 1984 Shoreliner Boat trailer. It was too easy to install. The video/suggestions at etrailer.com worked out perfectly and the harness went through the conduit like it was the OEM harness.12777



- A35W42B

ratingratingratingratingrating by: Shaun11/27/2010

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Great Product Nice wiring kit, super easy to re-wire 20ft boat trailer, for the price of this kit with the wishbone aka extra brown wire makes wiring marker lights a breeze without having to splice3753



- A35W42B

ratingratingratingratingrating by: Ivan01/30/2013

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For under 13 bucks you can't beat it. Worth every penny.64637



- A35W42B

ratingratingratingratingrating by: Kyle A06/04/2012

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Very good customer service andm fast shipping, very pleased 42765



- A35W42B

ratingratingratingratingrating by: L.W.Smith01/01/2011

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fast service the trailer light cable came in 2 days at Christmas time. I didn't expect it so soon. The right product at a good price. thx4875



Ask the Experts about this Optronics Wiring
Expert Answers about 35 ft. Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire - A35W42B                                           Do you have a question about this Wiring?


  • 2009 Smart ForTwo Wiring with Diodes for Towing Behind a Motor Home
  • Yes, you will need the diodes to tow your 2009 Smart ForTwo and have the taillights function properly while protecting the vehicles electronics. You will need to cut the vehicles wiring and splice the diodes in so that the diode will allow only one source of power to be applied to the vehicles lights at a time. The single spade connector coming out of the diodes is the connection to the vehicles bulb. The two connectors going into the diodes will be from the vehicles lighting system and the wiri
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  • Trailer Brake Wiring for Tandem Axle Brake System
  • I'm not sure what the sensor you describe is for. Typically trailer wiring is color coded so that right turn and brake light signal is carried by a green wire, and the brown wire carries the running light circuit. The brake output circuit is usually carried by a blue wire which travels to each brake magnet, where it attaches to one lead from each magnet. The other lead from each magnet will ground to the trailer frame. I'll give you a link to a typical trailer wiring diagram. You can find t
    view full answer...

  • How Does the 35 Foot Wishbone 4-Way Trailer Wiring Harness # A35W42B Function
  • The way that the 35 foot Wishbone 4-Way Trailer Wiring Harness, # A35W42B, works is instead of having 1 taillight wire (brown) that you would need to splice into in order to run to both taillights, this harness has two wires (one attached to each stop/turn signal wire). The wires are attached to each other (except at the 4-Way connector) so you cannot mix them up. This would be good for your application since you will not have to splice wires that could end up being exposed to the water. I ha
    view full answer...

  • Wiring an 8x10 Triton Aluminum Snowmobile Trailer with Lights that have Separate Ground Wires
  • Wiring the grounds for your tail lights and the 35 ft. Wishbone 4-Way Trailer Wiring Harness with 42 inch Ground Wire, item # A35W42B, is fairly simple. The 42 inch ground wire provided with the harness is normally attached to the trailer frame near the coupler. Doing this makes the trailer frame a convenient point to ground all of the other ground wires for your taillights and makes it possible to use lights that are grounded through the mounting hardware. This is demonstrated in our Trailer
    view full answer...

  • Does a 4-Way Wishbone Trailer Wiring Harness Require a Special 7-Way to 4-Way Adapter
  • If the RV has a 7-Way, blade style connector, you can use any 7 pole to 4 pole adapter like # PK12716. If the RV has a 7-Way round pin trailer connector, you can use Pollak 7 Pole Round Pin to 4 Pole Flat Wiring Adapter, # PK12742. The 4-Way wishbone trailer wiring harness, # A35W42B, does not require a special adapter, even though it has 5 wires. In a wishbone harness, the running light circuit is split at the connector with one wire (yellow/brown) going to the left side and the other (green
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  • Can The Jeep Trailer Connector be Used For Connection to Motorhome When Flat Towing the Jeep
  • No, if you plugged an extended trailer connector from the motorhome into the trailer connector on your Jeep you would create a short circuit situation that would damage both the Jeep and the motorhome. I would recommend using a bulb and socket wiring kit, # RM-155, to wire your Jeep, if there is room in the Jeep taillight housing to mount the extra bulb. If you can send me your Jeep year-make-model, I will be glad to check to see if there is room for a bulb and socket kit. If a bulb and so
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  • Wiring Stop Turn and Tail Light Circuits to a Trailer Light
  • Your trailer lights should only have one wire if the light serves only one function (tail light, marker light, stop/turn). The white wire shown in the photo that you attached is a ground wire and will not be connected to the tail light or stop/turn circuits. The bulb attached to your light housing looks like an 1157 bulb, which is a dual filament bulb that has two contacts for two different circuits. You should have two wires on the back of the light housing, one for the stop/turn circuit an
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  • 1997 Chevy K1500 Trailer Brake Lights Go Out when Running Lights are Turned On
  • This is symptomatic of a ground problem on the trailer. Ground problems normally show up when there is more load on the system. Applying the brakes with the running lights on will be the maximum draw from the lights. The connector on your trailer is a wishbone harness. It should have 2 running light wires, one for the left side and one for the right side. On a regular 4-Way harness there are 4 wires and the running light wire is split to got to each side using a jumper wire. Make sure the
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  • What Wire Gauge is Used on the 35 ft. Wishbone 4-Way Trailer Wiring Harness, # A35W42B
  • I went out to the warehouse and pulled a 35 ft. Wishbone 4-Way Trailer Wiring Harness, # A35W42B, and used a wire gauge tool to measure the wires. The copper wire itself is 20 gauge. If you measure the wire with the insulation on it then it is thicker but wire gauge corresponds to the strands not the insulation part.
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  • Wiring Wishbone Trailer Wiring Harness
  • The 5 wire Wishbone Harness with 4-pole connector splits the running light circuit into two wires. One wire would run along the drivers side of the trailer, the other along the passenger side. Typically, the running light circuit is only carried one one wire and at the rear of the trailer, you would need to split off a wire to feed the running light on the opposite side of the trailer. The wishbone harness makes the wiring job a bit neater and eliminates the need to splice in a feed for the othe
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  • Adding Separate Turn Signals to a Trailer Towed by a Honda Goldwing with a 5-Wire Harness
  • Based on the wiring functions you have given for the 5 wires on the bike it looks like it is already converter down to a 2-wire system. What you will need on the trailer side is a converter to separate out the turn and brake signals since they are presently combined. You will need # 118158. The green wire will attach to the green on the converter, yellow goes to yellow. Brown will bypass the converter. Then on the output side of the converter the red wire will need to be split by attaching it
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  • All Trailer Lights Blink With Turn Signal on 2007 Triton ATV Trailer
  • The fact that you have an aluminum trailer could be the problem. Aluminum does not make for a good ground. What I recommend is to located the ground wires at the backs of the lights and attach jumpers from the grounds to the main trailer connector ground. This is a common issue with aluminum frames, tilt trailers, and trailers with folding tongues. Also check the towing vehicle and trailer connectors for dirt and corrosion. Corrosion could cause a short or even a bad ground as well. The wo
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  • Rewiring an Airstream Trailer with New Wiring Harness, LED Tail Lights, and Reverse Lights
  • First, when you are looking at trailer wiring like # A35W42B it is always better to get one that is longer than you think you will need because you can always cut it shorter if needed and use the extra wire for something else. Since your trailer has reverse lights, if you need them to function you will need to have a 5-Way wiring harness on the vehicle and trailer. First, for the trailer side, you could use the 40 foot long harness # A40W5B. The blue wire, which would be used for the reverse
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  • Wiring Brakes On Tandem Axle Trailer
  • Typically trailer wiring is color coded. The brake circuit is usually a blue wire which travels to each brake magnet, where it is attached to one wire from each brake magnet. The other wire from each brake magnet will ground to the trailer frame. I have attached a drawing that shows how the wiring is typically run for brakes on a trailer. I have also attached a link to trailer wiring diagrams that may help.
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  • Troubleshooting 4-Way Flashers not Working Properly for a 2001 Dodge Ram and 2002 Horse Trailer
  • I will be happy to help. Since the issue is only present when your truck and trailer are connected; and the truck flashers work fine without the trailer connected, I would think the problem is associated with the trailer. It sounds like using the flashers while your truck and trailer connected overloads the system. The first think to check is to make sure that there is a good solid connection at the vehicle and trailer plug. Also, inspect the plugs and make sure they are in good working orde
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  • Easiest Way to Determine if a Tandem Axle Trailer has 2 or 4 Brake Assemblies
  • On a tandem axle trailer it is possible to have either 2 or 4 brake assemblies. If you only have 2 then they are likely on the front axle. What you can do is pull a front and rear wheel off or even just peak underneath and if you see brake assemblies (# 54801-005 linked as an example) then just count how many you need. I have linked a video showing a typical electric brake installation for you. Break away systems are very important and so is maintaining them. Make sure that all of its wiri
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  • How to Wire Electric Brakes on a Tandem Axle Trailer
  • If your trailer has 7 wires running all the way back to the brakes, then yes, you can tap into the existing wiring. Each of your new brakes will have two wires for the brake magnet. One wire is for 12 volt power to the brake magnets and the other wire should be grounded either to the trailer frame or to the main trailer ground wire. It does not matter which wire is used for power or ground because they are not polarized. If the trailer wiring is running down the left side of the trailer, the
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  • Short Trailer Side 4-Way Trailer Connector to Replace a Damaged 4-Way
  • Yes, there are some trailer side 4-Ways that have short leads or no leads that you could use. We have the Hopkins model # HM48110 that is 12 inches long. Another 12 inch long model is # 18004. And then we have Quick Fix connector # HMC20031 with no wires. I have included a link to these and other options for you.
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  • Wiring Electric Trailer Brakes with Magnets that Have 2 White Wires
  • It sounds like the magnets or their wiring could be bad. Your 2012 Chevy Silverado 2500HD is probably sensing the wrong resistance from the trailer brake magnets and that is why you see that warning message. When magnets have 2 of the same color wire it usually means that you can use either one for either function. The black wire with the 12 volt power should not be attached to the brakes. Only the blue wire should connect to the brakes. The other magnet wire should be attached to the tra
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  • Using Molded Trailer Connector # H20042 Junction Box # 38656 and Bulk Wire to Rewire Utility Trailer
  • To rewire your utility trailer, I'd start with a molded 7-way trailer connector, available in an 8 foot length, part # H20046, or a 3 foot length, part # H20042. The trailer connector will NOT wire color for color with the trailer wiring, so be sure to consult the wire color code chart on the product page for either length trailer connector. Wire the connector into a junction box, part # 38656. I've provided a link to a video that shows how this is done. You can use 4-conductor wire, part # 1
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Info for this part was:


Photos by:
Theodore B

Photos by:
Jackie C

Expert Research:
Michael L

Video Edited:
Zack K

Expert Research:
Robert G

Expert Research:
Michael H

Expert Research:
John H

Expert Research:
Rachael H

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