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25 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 25' Ground

25 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 25' Ground

Item # A25W2GWB
Our Price: $12.31
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A25W2GWB - Trailer End Connector Optronics Trailer Connectors
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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. 25 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 25' Ground part number A25W2GWB can be ordered online at or call 1-636-306-4830 for expert service.
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Optronics Trailer Wiring - A25W2GWB

  • Trailer Connectors
  • Trailer End Connector
  • 4 Flat
  • Plug and Lead
  • 21 - 30 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.


  • 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


  • Wire harness length: 25'
  • Ground wire length: 25'
  • 3-Year Warranty

A25W2GWB Optronics 4-Way Wishbone Trailer Wiring Harness with (2) 25' Ground Wires - 25' Long

California residents: click here

Video of 25 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 25' Ground

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

Video Transcript for Optronics 25 Ft 4-Way Trailer Wiring Harness Review

Hey everybody, how's it going Today, we're gonna be going over and showing you how to install the Wishbone 4-way 25 foot trailer wiring harness. So this trailer wiring harness here is gonna be the perfect option for any trailer up to 25 foot. Now, if your trailer isn't that long, it's perfectly fine. We would just go ahead and trim off the extra which is actually what we had to do for this particular application. But so long as it's not over 25 foot, this is gonna be a great kit for you. So this particular kit provides a standard 4-way flat, also referred to as a 4-pole trailer connector.

This is the most common type of trailer connector and the one you're gonna be using if you don't have electric brakes on your trailer. If you do have electric brakes, you're actually gonna be using a 7-way so you wouldn't use this. But for every trailer without a 7-way, it's gonna have this standard 4-way. This is the most commonly and widely used one. So a 4-way trailer connector is gonna transmit the running light circuit.

That's gonna transmit the stop and turn signal circuit for both the driver and passenger side. And there's also gonna be a pin on there for ground. So those are your four total of circuits there. This particular one is a Wishbone configuration. So what a Wishbone configuration is, it basically means there's gonna be two running lights one for each side.

Some 4-ways don't use that Wishbone and they just have a running light wire coming from the front to the rear. Just one wire and then they splice into the two running light circuits at the rear. So it really doesn't matter which you have. We can either run a running light wire for each side or just one and then tie it together at the rear. This one here, there's a wire for each side.

I kinda prefer this. It makes it a little bit easier. But again, you can use it no matter what your trailer has. So this kit has many different uses. Some people, their taillights are getting older. They're cracking, they get sun damaged and they're gonna replace the taillights. They figure that might as well replace the entire trailer wiring harness, which is what we did here. Or if you're building a trailer, it's gonna be an excellent option for that. Now over time, the jacket on those wires can get hard and crumbly exposing the bare wires underneath causing shorts. So that's a good time to upgrade as well. Really, it just really gonna be by age or if you're replacing other components. This is great kit here just to add to your complete set up there so you can make sure everything's working properly and you don't have any lighting issues down the road. So keep in mind, this wiring harness is compatible with both standard and LED taillights. We actually upgraded the LED taillights on this trailer. So it's gonna work great with both. The wire size is gonna be adequate for both of those types of bulbs. So now that we've gone over the wiring harness a little bit, let's go ahead and show you the installation. So first step of your installation, you're gonna go ahead and remove your old wiring harness here. You can see, we have a nice bundle here. It's quite messy. Now you can be as neat or as messy as you want when you're removing this. I end up just cutting a lot of this off 'cause I knew we weren't gonna be reusing it. So it was much faster just to cut everything off and then pull it all out. But now that we've got all the old wires out, we'll go ahead and start running the new ones. So next we're gonna take our wiring harness here and just untangle it as best as we can. So this is actually known as a Wishbone wiring harness. Now what a Wishbone wiring harness means is there's gonna be a running light circuit on each side of the trailer. So normally, they'll tie the running lights in at the back of the trailer, then they'll just run one wire up to the trailer connector. Here you actually have two brown wires for the running lights that go to the back of the trailer connector. So doesn't really matter which one your trailer uses. You can install this either if it had a Wishbone before or just had the standard one. So our two white wires here, these are for the ground. These run back to each taillight assembly. Our two brown wires, that's what we talked about. The Wishbone design. One goes to the driver taillight assembly. One goes to the passenger. And we have our yellow wire here, this will go to the driver's side. And then the green wire will go to the passenger side on the right. So what we're gonna do is we're gonna take our wiring harness here. Now I like to make things look a little bit cleaner. So I'm gonna take some wire loom and I'm gonna install it on the first couple feet of our wiring harness here. Just again, to make it look a little bit nicer. You guys don't have to do this, but if you have some laying around, it's worth the extra time to make it a little nicer. But once I get this on, I'm going to leave a couple feet at the tongue here 'cause you need to keep in mind that you need to have clearance to make turns and you want have enough to reach so you can reach your truck depending on your configuration. So give yourselves a little bit of extra wire here at the front. And the way you can do this to make sure that you don't short yourself, just kinda take it here and just wrap it around the tongue jack here or the trailer coupler. Just make yourself sure that you give plenty of extra. So now what we're gonna do is we're gonna route all of our wires from the front to rear here. So again, our wiring harness does kinda split in two. These three wires here with the green wire that's gonna go to the passenger side. And these three wires here with the yellow wire, that's gonna go to the driver's side. So just keep that in mind when you're routing them. But we're gonna go ahead now and get that done. And then we can show you how we did it. It's really gonna vary depending on how everything looks underneath. So the step by step really isn't gonna do you guys too much good because again, your trailer can be different, but the overall basis of it should be pretty similar. So we'll go ahead and show you that once we have it all done. So we've got our wires are routed now. Now right here just directly behind the jack tube, I used the little ring clamp here along with the self-tapping screw. That's just gonna secure our harness here so it's not falling down. But once I come from there, I'm gonna go directly down and then we're gonna be pretty much tying these to the bottom of the frame. So you're gonna see these little metal clips here. So I recommend picking these up with your wiring harness because there's really not a lot of ways to secure the wires to the bottom of the trailer. Granted that's gonna depend on your trailer, but most of the time, you're gonna have a flat lip on a frame rail. And the way these work is there's teeth on them. So you hammer them onto the bottom of the frame and there's a smooth side that you guide your wires through. So basically they just make a nice convenient way to hold your wires there without them dangling down, without requiring any modifications. Just a simple tap to the hammer and they're nice and secure. The teeth bite on there so they don't move. And then you can just use your wire to guide them through. But we're gonna use more of these here and just work our way down the frame rail. You can see our wire here. We have another one of those metal clips. And then from about this point on, we're gonna have to jump under the trailer. So we're underneath the trailer now and you can see we have our wire just tucked nice inside the frame rail here using those little clips that we showed you. And then for our particular trailer, we have these cross beams here. There's already holes drilled in there. We just enlarged them that way I could sneak the wires through that beam. If you don't have those, you don't have to worry about it. You can go around them. Again, a lot of this is gonna be specific to your trailer. Not everyone is gonna look the same underneath, but again, most of them are gonna have this frame right here so you can use those little ties. But we're just gonna keep working our way back to the frame. So we're gonna route our wire to about this point here. And then we're gonna come back outside the trailer because we actually have the clearance light that's gonna be installed here. Now, chances are you have several of these on your trailer. Some are gonna have more than others but the locations that you do have the clearance lights, here's what we're gonna be installing. It's just gonna mount up like so, so you need to make sure that you stop and give yourself some extra wire here whether you make your connections now or you make them at the end. What we did is we went ahead and cut our wires and we attached the two ends to one of these butt connectors. And then these two ends of the butt connectors, we're gonna attach to our light here. So we're gonna do that a little bit later. We're not gonna do it right now. If you wanna wait, you can just coil up, give yourself some extra wire to work with and then continue running your wire to the rear. But again, we need to do this each time that we have a clearance or side marker light on the trailer. You could have several so just be aware of that when you're routing your wire. So we don't have any more clearance or side marker lights. We just have the one on each side. So we can just now route this wire to the end here. Now this is a single axle trailer. So we're just gonna keep following our wire here. We have another cross beam that we went ahead. There's a pre-drilled hold there. We just drilled through it. So this area here around the suspension, the axle, you wanna be careful that you secure the wire. You don't want the wire getting tangled up in the leaf springs or anything like that. So directly over the axle, I have another one of those wire clips. Now you can use as many of these as you want or few as you want, but you do need to make sure your wire's not gonna be dragging on the ground. But from here, we're gonna go up and over the axle, we have another cross beam back there. And then directly after that cross beam, that's where our taillights are gonna be. So we'll jump outside the trailer. We'll show you where that wire comes out. So we've got our wiring harness. The end run back to where we have our taillight here. Now we're working on the passenger side. So again, we need to have that green wire. So what we're gonna do is we're just gonna simply connect our three wires here to the three wires coming from the back of the taillight. Now your taillight may be a little bit different in regards to wire colors, number of wires, because that's gonna come down to which specific taillight you have. But the three wire design of this one is pretty standard. This is gonna be most commonly used. So this is probably what you guys are gonna have as well. So we went ahead and just used something to secure our wire here, a little ring clamp, just so it's not dangling on the ground. So I'm kinda nut about this stuff. I always like to make sure that we have tons of security points along the way to secure our wire. That way it doesn't drag down, get tangled up in anything. I just like to go a little bit overboard even sometimes on securing the wire. But what we're gonna do now is we're just gonna attach our three wires here to our three wires here. We are, however, gonna make a ground jumper which will show you in the second. But in order to do all this, we are gonna need some miscellaneous butt connectors such as you see here as well as some electoral tape, some ring terminals. And if you guys have this at home, great. If you do a lot of wiring, chances are you do have these. They're pretty common. You could even pick these up individually in town. But we actually sell a kit here. That's gonna have all these miscellaneous connectors. All the ones you need and some of the ones you might not need. And it's also gonna have a crimping tool. So it's pretty cost effective. I would recommend picking it up along with your trailer wiring harness here. Just so you have everything right here when you need it. But with that being said, we'll go ahead and start making our connections now. We're just gonna strip some jacket off of each of these wires to start and then we'll begin making our connections. So our green, this is for the stop and turn signal circuit and then our brown, which is for the running light circuit. We can just connect those straight to one another using one of these butt connectors. You wanna use the blue ones here. I always like to twist those strands there. That way, they don't kinda fray and go to the side when you're sticking them in. So there's that one ane we'll have these running light wire. And get that crimped on there. And every time I crimp a wire, I always like to just give it a little tug. Hold on the butt connector and give it a little tug. Make sure it doesn't pull out. But we've got those two wires taken care of. Now we have our white wire which is just for the ground. So what I'm gonna do is I'm actually going to attach these together and then connect them to a ring terminal, which is this here. And then I'm going to screw that ring terminal into the frame of the trailer there to act as our ground. So you will need a self-tapping screw in order to do that. Well I think I'm actually just gonna attach it right up there. That seems like it's gonna be a good location for us. So there we go. That looks pretty good. What I'm gonna do now is I'm gonna take some of our electrical tape here. I'm just gonna clean up all these wires. You wanna make sure that you cover those butt connectors. You don't want any water getting in there. Basically, just making it look a little bit nicer. When we've got this side done, we're gonna do the exact same thing on the other side. Everything is pretty much the exact same except for the other side of the trailer has a yellow wire in our loom there. So now, as we said earlier, we needed to make some tie off points here for our running lights. So that's what we're gonna do now since we've wired everything up to the taillights. We're just gonna install our little clearance lights here. So this could vary depending on your particular setup, but usually there's gonna be a hole for your wires and then two holes for the mounting tabs there. So we're just gonna fish our wires down through there. Try to fish them out to the bottom as best we can. So now we're gonna go ahead and just secure our light using self-tapping screws. Again, this could vary depending on which actual clearance light you have, but most of them are fairly standard in regards to this two-hole design. And then once you have your light mounted and your wires ran down through here, you'll just crimp them and then secure them with electrical tape like you would normally. So now we're gonna go ahead and test everything out to make sure everything was done correctly. Now we have a tester box specifically for this but you guys are just gonna hook up to your vehicle there. Nice and simple. Gonna go ahead and turn on the taillights. We should see both the marker lights illuminated as well as the taillights at the rear. So we'll check both sides, make sure that's good. And then we will turn on our left turn signal. Perfect. Now we're gonna switch over to our brake lights. So the brake lights should illuminate the taillights on either side there. And then finally, we'll have our right turn signal. Make sure the right turn signal was illuminating there on that side as well. So looks like everything's working correctly for us. If you guys don't have any luck, just make sure to check all your connections with your butt connectors. That's usually the number one fail point and also check your grounds as well. So overall it's pretty easy. So you guys really shouldn't have any issues but just a few pointers there if your lights aren't working. So with all of our wires working correctly, that's gonna do it today for our look and installation of the Wishbone 4-way 25 foot trailer wiring harness..

Customer Satisfaction Score:

Customer Reviews

25 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 25' Ground - A25W2GWB

Average Customer Rating:  4.8 out of 5 stars   (156 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.


5 stars is pretty much a given here considering this is the only properly made trailer harness on the market. Doesn't hurt that it's well made also, glad I found it.


Nothing like leaving town at dusk only to find out at the first rest stop that your trailer lights are intermittently working. Ive used etrailer wiring harnesses in the past which surpassed the original harness.
Buy with confidence.

My wiring for my trailer has worked perfectly since I installed it myself a year ago. Just a tip for other users of this oroduct. I normally use the blue barrel connectors to marry my wiring to the lights. I would then cover the connection with shrink wrap to seal the connection. I found some marine grade barrel connectors that have the heat shrink built into the connector. One less step, and superior shrink wrap than what Id used orevious
Thomas - 11/22/2022


Great quality harness. The insulation is thicker on this than I could find locally, which means it'll stand up better in the semi-exposed conditions of the utility trailer I installed it on.


The wiring harness was easy to run and easy to hook up still working great.


This was the ONLY wishbone wiring harness I could find with dual full length grounds. I have never had any long term luck with using the trailer frame as a ground.
I can now ground my lights to a hard wired ground, which should last just short of forever!
Thank you for offering the perfect long term solution for trailer light grounding.


I know most folks are fine using the trailer frame as a ground for the lights. And, I’m sure that works fine for a great many. But if you want to create a bulletproof electrical connection this Left/Right split W/Ground Wire is exactly what you need. Copper core wire with reasonably thick insulation - easy to install, and pretty much guaranteed to work the first time. It certainly did for me.


One year and still working well on boat trailer that gets used weekly. Great product.


Grounding issues are always a problem with trailer lighting (in my experience), and it is great that there is a product specifically intended to provide grounding continuity from the light itself to the tow vehicles wiring. Too many systems rely on a short pigtail attached directly to the trailer and a connection at the trailer ball.

I am hopeful that this will be a long-term solution.


Separate wiring for each light - yes please. Only way I like to wire my trailers.


I liked this trailer harness because it has ground wires that runs the entire lengths of both legs. Good ground connections for all lights! Worked great!


Just as advertised. Easy to install and the individual ground for each light works great, I have not had any ground issues now. I use my trailer in salt water and no bad grounds anymore.


I really only needed the connector but am pleased that, after splicing it to the trailer harness with soldered joints, it works perfectly!


Hard to find item; Etrailer made it eas y!


Parts arrived quick and were exactly as advertised! Great product to make trailer wiring easier.


Quality plug and wire. Lights still burning bright


I had a hard time finding a 6 wire to a 4 way plug this is what my trailer had so I wanted to replace it with what it had originally could of used the 5 wire to 4 way plug but wanted to replace what it had so thank you for carrying it and for the nice prompt delivery


Perfect length for my boat trailer. The ground has been faulty on it so it was great to have a ground wire back to each light. No more light issues.


Great to have a separate wire, on each side, for running lights and ground


I just wish is was a more durable gauge wire. Also, the copper wire is NOT tinned so it won’t hold up as well in a salt water environment. Not a bad product but don’t use it for a boat trailer on the coast.

This Optronics Wishbone Style wiring harness uses 18 gauge wire for the ground and 20 gauge for the lighting functions which is pretty common for wiring harnesses. I recommend to use heat shrink connectors to insure your connections are not exposed to moisture with part # DW05743-5
Deka Heat Shrink Butt Connector - 22-18 Gauge - Nylon Insulation - Red - Qty 5
-- Etrailer Expert Heather A - 03/07/2022


Used this to install lights on a curt folding cargo carrier, was good to have 2 ground wires(white) and 2 parking light wires(brown), to avoid extra connectors that would cause corrosion problems


Your site was very easy to navigate. Products were well explained. Everything I ordered came in 3 days with no problems.Tracking number was sent as soon as processed. I will buy from them again.


This is perfect for tilt trailers and others with bad grounds through the hitch to the taillamps.


Glad somebody makes this type of harness with full-length ground wires on each side of the trailer. Wire guage is about 18 according to my Klein strippers. It appears to be copper. The plug lists Taiwan as country of origin. I'm happy with the product for the price. With a careful, proper installation, this should provide trouble-free service for many years. I gave 4 stars. With a more substantial plug-to-wire attachment, I would give 5.


I purchased this wiring harness to replace one for my cousin on her trailer.
Everything was as it should have been..the install job was much easiernot having to battle the harness as well as the old trailer.
One year later and everything is still A Ok.

After a year of use, wiring harness has held up well. No issues to speak of. Money well spent.
Russ S - 06/08/2021


Perfect fit

Show More Reviews

See what our Experts say about this Optronics Trailer Wiring

  • Should Ground Wire of Trailer Wiring Run to Frame of Trailer or Back to Light Assemblies
    Either option will work fine. If it was my decision to make I would ground the trailer wiring on the frame near the coupler since that's easiest and just as effective, but if you had an aluminum frame trailer or a dump trailer you'd have to run the ground wire back to the light assemblies so that they ground sufficiently. Most trailer lighting grounds through the mounting hardware which allows for an easier install so grounding the trailer connector to the frame at any location gives...
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  • Grounding a 4-Way Wishbone Trailer Connector
    The 4-way harness you looked at, part # A25W2GWB, has a ground wire. It's the white wire which is kind of hard to see in the pictures. This is a wishbone 4-way so there are two brown wires for running lights; one for each side of the trailer. Then the green wire is brake lights and the turn signals for the right side and the yellow wire is brake lights and turn signal for the left side.
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  • How To Wire 4-Pole Harness with 5 Wires
    I can't comment on specific wire colors but it sounds like you're referring to a wishbone trailer wiring harness like part # A25W2GWB which has five wires and four pins on the connector. There will be two running light wires (one for each side), a left stop/turn wire, right stop/turn wire, and ground wire. The running light wires are usually brown/yellow and brown/green whereas the left stop/turn is yellow, the right stop/turn is green, and the ground wire is white. If your colors don't...
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  • What Type of Trailer Wiring Does Boat Trailer Typically Have
    Boat trailer 4-way trailer wiring is done in the same way as other 4-way trailer wiring. Sometimes boat trailer will use 5-ways instead if the trailer has surge brakes and the actuator has a reverse lockout which allows the trailer to back up without brake application. For that we have the part # HM37908 which comes with a 5 foot harness.
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  • Troubleshooting Wishbone Wiring
    It sounds like the running lights are the issue as they are not functioning with your wishbone harness. I'm not sure what harness you have but a 4-way wishbone like # A25W2GWB will have two taillight wires, one for driver side stop/turn and the other for passenger side stop/turn. If your lights are not working, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong...
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  • Tracker Boat Trailer Wires With 7 Wires Connecting Into A 4 Pin Plug
    It could be possible that your 2012 Boat trailer is wired with a wishbone style harness. Similar to Item # A25W2GWB. This type of harness just allows the installer to run each side separate rather than splicing and running extra wires across the bottom of the trailer. Your best bet may be to test each wire function before cutting. You cannot get trailer brakes from a 4 pin connector which is why I am leaning more toward it being a wishbone. Once you determine the proper functions all you...
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  • Replacement 4-Way Flat Trailer Wiring Harness For 10' Trailer
    This will depend on your trailer and how you prefer to wire the lighting. For a steel trailer you can use a 20 Ft 4-Way Trailer Wiring Harness # A20WB. This harness only has a 30" ground that will attach to the trailer frame and all the lights will ground to the trailer frame to complete the circuit. The 25 Ft 4-Way Trailer Wiring Harness # A25W2GWB has a ground wire that runs the full length of the frame. With this harness you will not use the frame as a ground circuit so all marker...
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  • Recommended Trailer Wiring Harness for a Boat Trailer
    The Optronics 25 foot 4 Way Wire Harness # A25W2GWB will be a good option. This will generally have enough length to cover most trailers. I will also recommend adding in a few of the Spectro Self-Stripping Connector with Waterproof Sealant # SWC501746-1. These will make splicing into the # A25W2GWB significantly easier. Especially for your side marker lights.
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  • Troubleshooting Trailer Lights on a Jayco Camper Flashing All Lights When Running Lights Are On
    It sounds like you have a short in your electrical harness. You will need a Test Light # PTW2993 to try and determine where the short is located in your harness. First begin by checking with the connection on your tow vehicle. You want to determine if all your lights blink when your running lights are on. If on a 4-way flat connector the female connector closest to the single male connector is the terminal that powers the running lights of the trailer. The center female connector is...
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  • Wishbone Trailer 4-Way Wiring for Aluminum Trailer
    We don't have a version of wishbone trailer 4-way with wiring like part # A25W2GWB that also has a second set of ground wire for aluminum trailers so your best option would be to go with additional wire like part # 16-1-1 which we sell by the foot.
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  • Can 7-Way and 4-Way Both Install on Trailer for Separate Wiring Circuits
    When you say rear lights do you mean like utility lights so that you could see in the dark? If so you could just use the 12 volt accessory circuit of the 7-way to accomplish that. But aside from that you certainly could have two different connectors on your trailer for two different sets of lights. For a 7-way plug all you'd need is the part # 277-000143 and then for a 4-way part # A25W2GWB for 25 feet.
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  • Recommended 4-Way Flat Wiring Harness For an Aluminum Trailer
    I prefer to us a harness like the 25 Ft 4-Way Trailer Wiring Harness # A25W2GWB as it has a ground wire that will run the full length of your wiring so you will not have to tap into the trailer for a ground source. This will help you to waterproof your connections to your tail lights using Heat Shrink Butt Connectors # DW05744-10 and reduce the chances of corrosion/oxidation between the ground wire and trailer frame leading to issues with the lights later down the road. Since the front...
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  • Troubleshooting Left and Right Stop/Turn Trailer Light Functions Not Working
    Since the issue is with the brake and turn signals that narrows it down to the green and yellow wires on your trailer. The green carries the right stop/turn signals while the yellow carries the left stop/turn signals. It could be that the lights themselves are messed up or have a bad ground but since it sounds like all of the lights on both sides is the problem I bet the wiring for those circuits needs to be repaired or replaced. You can use 16 Gauge Wire # DW02359-1 and Heat Shrink Butt...
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  • Is Wishbone 4-Way Required for Trailer With 4-Way but 5 Wires
    Yes you should! You are on the money with what you need, a wishbone-style 4-way wiring harness for your trailer. With this style, the white is ground, yellow is left turn/brake, green is right turn/brake, and the two brown wires are the running light wires. I'm not sure the length you need though, or if 35 feet might be too long, which is the length of the 4-Way Trailer Wiring Harness - Wishbone Style # A35W42B. We do have different lengths available, which I'll list for you just in case...
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  • Replacement Wiring Harness For a Adams Drift Boat Trailer
    The 25 Ft 4-Way Trailer Wiring Harness # A25W2GWB would be the closest harness we carry for your Adams drift boat trailer. This will require you to splice the 3-Wire Pigtail # A45PB for your Optronics Fleet LED Trailer Tail Lights # TLL12RK as we do not carry a harness that has the connectors you need already spliced into the harness. I recommend using the Deka Heat Shrink Butt Connector # DW05744-5 to make the connections. You will need 2 of these 5 packs to get the 6 connectors you need....
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  • Recommended Oval Taillight Wiring Kit for Kayak Trailer
    I do have an option for you though we don't have an all inclusive wiring kit with oval taillights. I recommend using the Optronics LED Trailer Tail Lights part # TLL12RK with the 25 Ft 4-Way Trailer Wiring Harness part # A25W2GWB and the Optronics LED Clearance or Side Marker Trailer Light part # MCL0040ABB. In order to hook-up to a seven way connector, you'll also need an adapter like the Pollak 7 Pole to 4 Way Connector Adapter part # PK12716.
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  • Trailer Wiring Harness Compatible with Peterson 435800 Trailer Stop/Turn/Taillight
    We don't offer a plug and play trailer harness that would plug directly into the Peterson # 435800 trailer taillight. The lamp includes a 3 pin pigtail that would plug into the rear of the lamp which would wire directly into the trailer wiring. If you need a 4 pole harness for your trailer, we offer them in varying lengths. • For a 20 foot harness, use part # A20WB • For a 25 foot harness, use # A25W2GWB • For a 30 foot harness, use # HM48265 • For a 35 foot harness, use # A35W42B To...
    view full answer...
  • Parts Needed to Add Wiring for Trailer Lights and Brakes
    I recommend using the etrailer Trailer Wiring 7-Way Upgrade Kit w/ Junction Box and RV Style Connector # e99011 to start off. This gives you a 7-Way connector and a clean and organized way to connect all of your wiring. Then for the wiring for your lights I recommend using the Wishbone Style Wiring Harness # A25W2GWB. This is 25' long which will give you enough for the length of your 16' trailer plus some extra wiring to make sure you have enough to connect all of your lights. You will...
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  • Availability of 16 Gauge Wire for Trailer Lights
    The Optronics 4-Way Wishbone Trailer Wiring Harness # A25W2GWB that you referenced has 18 gauge wire for the ground and 20 gauge wire for all of the lighting functions. I check with all of the other wishbone harnesses that we have and they all use similar gauge wiring none of which is 16 gauge. For 16 gauge wiring you can use the Deka Bonded 4 Wire # 16-4B-1 which is sold by the foot. I recommend using heat shrink butt connectors like part # DW05744-10 and the Quick-Fix Replacement 4-Way...
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  • Parts Needed To Install A Trailer Tail Light That Has 4 Wires
    I am unable find any lights like these that have the 4 wires for attaching to the light. You should be able to test each of the wires for their function using a 12 volt battery and connecting the wires directly to the terminals. My only concern is that your lights were set up to have separate brake light functions and that is why you have 4 wires. If that is the case and you want the lights to function properly you will have to run additional wiring and components as opposed to just using...
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