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Plug and LeadItem # A35W42B
Retail:$16.69
Our Price: $15.36
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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.
Features:
Specs:
Manufacturer Cross Reference
Harness will work as an exact replacement for:
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Video of 35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Today on our trailer, we'll be doing a rewire using the 35' Wishbone 4-way trailer wiring harness with 42" ground wire, from Optronics, part number A35W42B. Now we went ahead and already removed all the old wiring on this trailer before we began this video. So now we're ready to start with a clean slate. To begin with, we're going to go ahead and tape the two ends of the wiring together to make it easier to feed back to the back end of our trailer. We're going to go ahead and work our way through and tape up about every 5' to 6', just to help keep the wiring together, so when we pull it through the holes already in the trailer, it'll make things a little easier. Now we're going to begin up here at the tongue.
We went ahead and we're going to add about a 4' or 5' section or wire loom, part number 459075-1. We're going to use about 6' total. Now that we're got the loom over the end of the wiring, we're going to go ahead and use some electrical tape to help tape it up. On this particular trailer, we're not going to use the wishbone style, as we're going to run both wires down the same side of the driver's side of the trailer, and then take the passenger side and run it across the back, as this was how the trailer was already wired previously, so there's already holes in the trailer for us to route the wiring. Now we also need to find a suitable ground location, where we use a self-tapping screw and the ring terminal already on the wire.
As you can see here, we found a good cross member on the trailer that we'll be able to put a self-tapping screw in to make a good ground. We're also going to be using some 1/2" loom clamps, which are part number A0500. Now we'll go ahead and finish pulling the wires to the back of the trailer. As you will notice, wherever we went through the trailer, we went ahead and used a little electrical tape where the wires went through the trailer to give it a little extra protection, so when the wires move up and down they don't wear through. We also went ahead and put a zip tie on each to help keep the wires from moving too much.
Now that we've got the wires routed to the back of the trailer, we're going to go ahead and pull the green and the brown wire over to the passenger side of the trailer. Now this wiring harness is much longer than we actually need for this trailer, but we're going to go ahead and route the wire around through the center of the cross member in the back, in case if we ever have to change the lights we've already got some longer wiring there. We'll cut the wire to length on the driver's side, split apart the two wires, and strip back the end. Now the lights on this trailer have three wires coming out of them, a red, a black, and a white. The black wire will be connected to the brown wire, which is the running light wire.
The red wire will connect to the yellow or the green, depending on which side of the trailer you're on. And the white wire we'll put to a ground. We'll go ahead and connect the yellow and the brown wire with the red and the black wire on the driver's side. To do this, we'll use some bud connectors, part number 05730-5, and some electrical tape. You'll also notice that we used about 6" of wire loom here, just to give a little extra protection for the wires coming out of the bottom of the lights. Once we connect the bud connectors on the driver's side, we're going to go ahead and slip a loom clamp over the bud connectors and wiring. When we put our self-tapping screw in, we'll go ahead and slip the ring terminal from the white wire, which is the ground wire for this light, over the screws so that we can make our ground here. Now we're ready to go over to the passenger side, and we'll repeat the same process. But on this side we use the green wire to the red and the brown wire to the black, and again the white wire will go to the ground. We use the same thing where we use two bud connectors, a loom clamp, as well as the self-tapping where we use that for the ground. Now that we have all our connections made and the wire zip tied up, as well as clipping off any excess zip ties, now we're ready to go ahead and test our light functions. To do this, we will use a tester. We'll test to make sure that the running lights work, the right turn, the left turn, as well as the brake lights. As you can see here, all the light functions are working properly. And with that, that will conclude our installation of the 35' Wishbone 4-way trailer wiring harness with 42" ground, from Optronics, part number A35W42B.
Average Customer Rating: 4.9 out of 5 stars (362 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.What was needed to rewire boat trailer. 640879
Harness was exactly what I needed and wanted. Most try to use a 4 wire system (which will do) and then split the running lite wire. 8 times out of 10 they can't get it right and end up taking it somewhere for fitting. etrailer.com had the exact item. Life is good again. quick shipping too. 615822
I recently bought a 2004 Trailstar boat trailer for a boat with a seized engine that a friend is giving me. The trailer was a great deal, but they told me the lights worked and they didn't. The connections were all corroded, none of the side lights were hooked up, and there wasn't enough slack in the existing harness to connect anything to it. Your harness was plenty long and only $15! I just wish that the ground wire was as long as the other wires. The ground wire only reached to the front part of the trailer and there's a hinge with rubber bushings halfway along the tongue. I had to ground the front part of the tongue to the part after the hinge. And then I used the ground wire in the old harness to ground the taillights. 619248
Website was very helpful as to finding the correct part numbers. My order processed and was shipped in great time! This is my first time dealing with this company, but not my last. I’m recommending to all of my family and friends! 609437
The plug looks and feels solid! This is the only place that had a long enough wiring harness to do what I needed. Shipping was also very fast! 471215
After one year, It is still working great! It makes all the difference having long enough wires to where there is no splicing on a saltwater boat trailer.
Eric - 01/29/2019
I want to thank you for all your help with my trailer you were more helpful than you realize. So this is my trailer for a 22' Flats Cat shallow draft Catamaran. I totally dismantled my trailer and buffed by hand with a wire buffer and sand blasted in some spots and applied multiple coats of some very expensive galvanize paint (Z.R.C.). I installed all new C. E. Smith Carpet (about 80'), seven new LED waterproof lights, new springs, new equalizers, new tongue jack, new wench, new safety chain, new chain brackets, all new SS hardware and a 35' long wiring harness. I was able to send only one review with a picture of the safety chain and brackets. I'm having a little trouble with the rest..oh some of these items were bought locally or from your competitors, until I found ETRAILER. Your prices were cheaper for the exact same things. Your helpful how to videos were helpful. And Rose, your personal helpful knowledge made my buying experience very pleasant, I actually enjoyed talking to you! Thanks to ETRAILER and specifically to Rose G. 497941
Fix perfectly and all lights work great. Thanks Etrailer 568434
I am very satisfied with my experience with etrailer. The parts I received appear to be very good quality. I have not installed them yet though as I am waiting on Hurricane Michael to pass through. However the lights do seem to be very solidly built. I needed this style and etrailer was the one that had it. 572964
Great product. Nice to have two running light wires (brown pin 2)so I could feed running lights and license light without splicing wires... 158701
Perfectly
Tom F - 10/31/2015Customer 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 Lang 4218
Perfect description, Amazingly fast delivery, Wonderful communication. Will for sure be shopping here again. 225773
Awesome product worked great will reccomend to my friends to buy products from here.
Willie - 09/15/2016Perfect! Just what I needed!! I could only find a harness plug with one brown wire (4 wires total) at my local stores. I "googled" the problem I had (my harness plug had 2 brown wires). A rep from etrailer had answered someone's same question on a message board. It was a detailed explanation as to why one would need this part. Then the rep put a link to the etrailer site. And there is was, the harness plug with 2 brown wires (5 wires total) and at an agreeable price to boot!!!!! And now I know about the etrailer website!!!! 210017
Worth it's weight in gold when it came to wiring my trailer. I bought this for a homebuilt camper project and this made wiring my lighting simple. Although, my only complaint would be the short 42" ground wire. I'm a firm believer in not using the trailer frame for grounding - I consider it a sloppy installation practice. I'd rather run the extra wires and have dedicated ground wires run to all lighting 359697
This is a great quality product. Moreover, I initially purchased a similar product from Walmart which was 20 feet long, but then I checked with etrailer and was able to obtain an identical product that was 35 feet long for only a couple bucks more - a much better deal. This gives me more latitude to run the wire without worring that it might end up being too short. I'm rewiring a flat bed trailer and plan to run the wire inside of 1/2 inch pvc so it will be protected and I'll never have to do it again. 185237
this product was absolutely prfect. I was very satisfied very short time for delivery.I do and always will shop for all my trailer needs at etrailer .com. They are the best 572165
Excellent product and shipping! Let me say all I could find everywhere was 25 ft. The extra 10 feet I get with this item NOW allows me to fix the short in my utility trailer. Thank you so much. 146168
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
Absolutely no issues still very happy.
Joel T - 03/23/2015Because of a break in the wiring of my pontoon boat trailer, I needed to replace or splice it. For reliability, I decided to replace it. I had a full harness but discovered that it was too short and the wire was very thin. I needed the wires to be more than 30 feet. I ordered this one on trailer. The harness is 35 feet long which left me a couple feet to spare and is excellent quality. I used a sewer snake to pull the wire inside the tubes of each side of the trailer and was back in business is a couple of hours. I have ordered several times from trailer. They have parts that no one even dreams of carrying with great prices. The website is full of great information. 492704
Top quality, perfect length, simple wire harness. 224248
All the products are fabulous!! Thanks for following up with me. They are in use regularly.
JP - 09/13/2016Great delivery and cost was low. Exceeded my expectations. Easy installation. Note: I have a patch work steel frame and have trouble getting a good ground. Wooden trailer bed with segmented (and rusted) steel frame. So I soldered a long wire to the white ground wire, and ran the entire bundle to the rear. I ran a ground from each light directly to my new ground wire. Works great for my special application. I love Etrailer. 140049
Everything is fine and I want to thank you for your fine service. The trailer is working very hard for the family.
Fred C - 07/09/2015High quality connector has held up well being in the weather 24/7. 659701
Works great!! 658506
Parts are good fit great no problem You get what you ordered thanks 658338
These are what are needed, but finding them on your web site was a little tedious. 655963
Added folding tongue to my boat trailer and had to rewire. This was an exact match to what came stock on my trailer and worked great. 652972
The wires are copper so should last a long time. There was plenty of wire length for a 20' boat trailer. 651141
Wires are much better than the others I have used. Have not installed yet but should work great. Nice having wires split so they run down each side of trailer. 642173
There is really not too much to say about these wires - they work as they should, and the price is better than at the hardware or any auto parts store. 640825
The product was as described and of good quality. I rewired a 2000 boat trailer and it worked great. I just wished I would’ve order LED brake/tail lights at the same time. After rewiring I discovered the lights were bad. Very satisfied with the product and the fair price. I have several things from Etrailer and have been satisfied with everything I ordered. 638641
Had it a year. Still works flawlessly. Good product 638549
Tired of the big box retailers . E Trailer always has a good price and constant service. When I need something I just log on and know its going to be delivered. Never any running around or headaches to deal with. Great team guys keep up the good work!! 637984
Very polite and shipped order right away. Took less time than stated to arrive and was shipped to the address requested. Highly recommend. 637552
Product worked quite well - much better than previous items of a similar nature from other companies. Will definitely look to etrailer for future needs! 634744
Is a good simple product that worked well for my sailboat trailer. A year in and it's survived several dunkings. In retrospect it probably would have been good to put the wires in some plastic conduit or something similar since they hang down just a bit but that doesn't change that the harness worked great. 628293
Good quality. 628043
Worked great 620376
These lights and wires have worked flawlessly for over a year. I used a cheaper set from the discount hardware store and they kept failing. You get what you pay for!! I will order all my trailer needs from etrailer.com in the future. 619817
Excellent product. Makes wiring a trailer very simple. Super fast shipping. 613835
Wiring arrived in great shape and just what I needed. It will do the job rewiring a boat trailer quite well. Only 4 stars because I wish the ground wire was 5 feet long. 42" inches doesn't quite make it. You guys have a great website. Very proactive for your customers. I'll be ordering again. 612941
Wiring was just as described 611748
Ordered this harness for an old 16x8 trailer. It was a blessing and an easy install. Thank you! 608604
Great price on hard to find item.. 606669
Great products and great shipping 603779
Plenty of wire to do the whole job without splices 600003
can't beat the price 599454
Timely order processing and great quality! ?? 593203
This is exactly what I needed for my pontoon trailer! FAST SHIPPING TOO! 589523
Excellent quality! Heavy make connector end. Wire insulation that wont crack and fall apart in a years time. 584935
Ordered a wiring harness and connection jack for my boat trailer from ETrailoer.com , and product was top of the line and was shipped and delivered as ordered, very happy with ETrailers online sales . Plan on installing on my trailer as soon as weather breaks . Will eliminate problems i ve had with wiring . 582572
Received but not yet installed. Great quality. 35 feet long...excellent!! Using it on a vintage travel trailer. Highly recommended! 581155
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