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25 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire
Optronics

25 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire

Part Number: A25W5B
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$32.24
Trailer Wiring
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5-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. Auxiliary wire signals trailer brakes to disengage when in reverse. Great Prices for the best trailer wiring from Optronics. 25 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire part number A25W5B can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Wiring - A25W5B

Highlights

  • Wishbone-style harness: Simplifies wiring with split tail light wires for easy installation.
  • Auxiliary wire inclusion: Blue wire connects to backup light circuit for braking control.
  • 25' wire length: Offers ample reach for most marine trailers, enhancing versatility.
  • Color-coded wires: Eases installation with clear guidance for each wire's function.
  • 5 Flat connectors: Ideal for trailers with 21-30 ft length needing 5-way system integration.
  • 20 gauge wiring: Ensures reliable performance and compatibility with standard connectors.

Features to know about

Seamless Trailer Light Control: 5-Way Trailer Harness with Wishbone Style

The 25 Ft 5-Way Trailer Wiring Harness from Optronics provides a straightforward way to control your trailer light functions with ease. Perfect for boat trailers and others with hydraulic or surge brakes, its wishbone-style design simplifies the installation by splitting the tail light wires. This lets you run separate wires to each side of the trailer without needing additional jumper wires, ensuring that your lighting is always reliable.

Reversing Made Easy: Auxiliary Wire to Signal Brakes

Forget the anxiety when backing up with a trailer. This harness includes a blue auxiliary wire that connects to your tow vehicle's backup light circuit, signaling the trailer’s brakes to disengage when reversing. This feature is particularly beneficial for trailers with hydraulic actuators equipped with an electric lockout, providing smooth and stress-free reversing every time.

Simplified Wiring: Color-Coded for Hassle-Free Installation

You'll breathe a sigh of relief with the color-coded wiring, which makes installation a breeze. Each wire is distinct: white for ground, brown for tail lights, yellow for driver’s side stop and turn, green for passenger side stop and turn, and blue for the auxiliary wire. It's all about making DIY installation straightforward and efficient.

Marine-Ready Design: Ideal for Boats and Saltwater Use

Built to withstand harsh environments, this wiring harness is well suited for boat trailers, particularly those used in saltwater. Its high-quality materials ensure minimal corrosion, even with frequent exposure to water, and restore your trailer to a reliable towing vehicle, meeting today’s trailer wiring standards.

Tailored for Variety: Versatile Replacement with Wide Compatibility

Whether you’re upgrading or replacing an existing harness, this product provides a tailored fit and versatility that handles various needs. It's compatible for straightforward swap-outs with other popular models like Truck Lite #002275, making it an ideal solution for replacing old or inadequate systems with a robust and convenient harness.

Perfect Fit for Long Trailers: Length to Spare

With 25 feet of durable, 20-gauge wire, this harness is perfectly suited for longer trailers, offering ample length to reach end-to-end without splicing. It also includes a 30-inch ground wire and a 5-foot aux wire to cater to specific wiring requirements. For large trailers, having enough wire to work with eliminates the stress of complicated extensions and ensures a clean, hassle-free installation.

Specs

Wire Specifications

  • Wire harness length: 25'
  • Wire gauge (all): 20
  • Ground wire length: 30"
  • Auxiliary wire length: 5'

Manufacturer Cross Reference

  • Harness will work as an exact replacement for: Truck Lite # 002275

A25W5B Optronics 25 Ft 5-Way Trailer End Wishbone Wiring Harness - 30" Ground - 5' Blue Wire

Alternate part number: A-25W5B




California residents: click here


Customer Satisfaction Score:

Ratings & Reviews

4.6

61 reviews
5-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. Auxiliary wire signals trailer brakes to disengage when in reverse.

by:

Works very well. Ran the wires down the tubes of my boat trailer and installed the tail lights and runners very easily. Cut the excess wire off and lights are solid after one year on my boat trailer.

Brooke M. profile picture
Etrailer Expert

Brooke M.

3/12/2025

So glad to hear that, Derek! We just had a tutorial here at the office and I was blown away at how straight forward it can be. What do you haul with the trailer? Anything fun?



by:

I installed this on a Moomba boat trailer and it fit perfectly. Installation was easy enough. Paired with e-trailer's submersible LED trailer lights, the parts went together for a seamless, durable system that will last for years to come. The boat trailer looks like new again! Thanks e-trailer!!



by:

Item is just what I need to rewire my 99 Triton boat trailer. Item is of great quality and at a competitive price. In addition,the item was shipped and delivered fast. Lastly, staff members are courteous and willing to assist with any questions and concerns before ordering and upon arrival. I will definitely do business with in the future.



by:

So, I converted my brand new Loadrite trailer to LED'S and wanted to add up a reverse light. I purchased this 5 wires trailer light harness to do the trick. Very good quality and the color code stayed the same. Had no problem what so ever and was an easy swap. I soldered every wires and protect them with heat shrink tubing and that should last a very long time.
Thank you.

Vincent profile picture

Vincent

5/19/2019

George, after one year, Im pleased to say that your product still perform flawlessly. All is good with the harness and would recommended to all of your potential customer. Thank you for the follow up a year later, really show whos taking care of his customer. Again, thank you,



by:

Just as described, good harness at a good price.



by:

I purchased this set to rewire my race car trailer and add reverse lights to the pigtail... wiring went flawlessly and there was plenty of wire and connectors are good quality... even had a dog chew on the trailer end and other than a slight ground issue, works perfectly.



by:

Very high quality wire, easily stripped outer and very good quality copper wire within. All connections were spliced and soldered, covered with heat shrink.
Easy to use. Again, having back-up is a game changer. Long overdue and nice to have affordable quality product to upgrade with.



by:

Got this wiring harness for my small camper to completely re wire it. Also got rheTLl28RK combination trailer lights. Nice and bright!



by:

Average quality, very good shipping time plus hard to find item but etrailer had it.will definitely be buying from you guys in the future.



by:

5-wire harness kit is exactly what I need. I hate splicing wiring runs because, in a saltwater environment, this only leads to more chances for corrosion. The only thing that would be better is the complete round plug set-up.
My boat and truck are happy!



by:

Easy to install perfect length and works great!! Can’t see it on the trailer because I have it heat shrinked and wire loomed for protection



by:

shipped fast, exactly what I ordered. Great quality



by:

This product was exactly what I was looking for. I was having issues with my trailer lights on a 20 year old trailer. I decided it was best to just remove all of the old wiring and start off new. This product took care of any concerns i might have had by just replacing a wire or two. All of the lights and connections are excellent and I don't worry about something not working.



by:

After having this in my garage for about 6-9 months I finally got around to rewiring my trailer with this harness. The harness has been on the trailer for 4 months and it has been solid. I would recommend getting longer than you think you will need. IE if you have a 25 ft trailer get a harness that is ~30 ft.



by:

Wiring is great. Was given 2 truck tail lights with back up lenses so I needed to rewire my trailer for a 5 wire system. My trailer is 30 years old so it needed a complete makeover. e trailer was a great help. They had a 5 wiring harness and a duel trailer connector for my Jeep. I needed a 4 wire and a 5 wire adapter to fit the Jeep to 2 trailers I own. They had what I wanted and it was delivered in 3 days.



by:

Everything I ordered is in the box! Excited to get it all installed.



by:

This wiring is almost plug and play! It is already set up with double brown wires to meet today's trailer wiring standard. And with the hitch-end flat plug and ground ring already in place, it is a quick installation. Thanks.



by:

Great, I think I will enjoy the install, with all that's going on in the World. Thanks for the extremely fast delivery and help with making my selections!


I did make one mistake, the Thin LED Light I order; I think I need to order the base bracket as well!



by:

Needed to replace my wiring on my 18 foot boat trailer. This did the job. Easy plug and play.



by:

Product works well. Installed on boat trailer used primarily in saltwater. Corrosion is minimal.



by:

I. ordered this along with marker lights its been a year and they work great.



by:

I have been in sales, retail, B2B, and sales management for over 30 years. E trailer has the whole package - excellent customer and sales service, great products, videos for those of us who like to do our own work, fair prices, and my go-to for my trailer needs.



by:

Fast shipping and great product. Easy to install on my boat trailer. Will test the longevity of this product over the next several years. But overall very pleased, and etrailer is a wonderful company.



by:

WORKED GREAT.



by:

Worked exactly how I needed it to.


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Show More Reviews

See what our Experts say about this Optronics Trailer Wiring

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    Yes, the LED Trailer Light Kit part # TL16RK, Light Guide LED Backup Light part # BUL602CB, 25 ft. Wishbone 5-Way Trailer Harness part # A25W5B, and Right Angle 3-Wire Pigtail for Optronics Trailer Lights part # A47PB will all work together and give your trailer reverse lights. The Submersible Tail Light Kit part # TLL36RK comes with a 4-way wiring harness and since you will be using a 5-way wiring harness, the more cost effective solution would be to purchase the Waterproof, Over 80"...
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  • Do You Carry a Jacketed Cable for Trailer end With 5 Flat Connector?
    Hello Todd, We do have some 5 flat trailer end connectors that will work for you: - 24" # HM47913 - 5' # A25W5B I do not have anything in a jacketed cable, what you could do is purchase # DW04906-1 by the foot and connect the # HM47910 using butt connectors like # DW05744-5. I usually do not like doing it this way because the more connectors you have the more likely you are to develop a weak spot. What are you needing this for? What connectors do you have on the vehicle end? Just...
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  • Replacing Trailer 5-Way Connector That has 7 Wires
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  • Replacing 5-Way of Trailer that Has Two White and Brown Wires
    What you have is a wishbone style of 5-way that has the ground and running light circuit split for either side of the trailer. You can replace this setup with one that has a single wire by running both of the wires on the trailer side to the new connector if you wanted. We have the part # A25W5B which has the ground circuit wishboned but you'd need to run the two wires to the single running light circuit.
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  • Replacement Trailer Wiring Harness For a Boat Trailer Using a 5-Way Flat Connector
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  • What Should Be Done With Extra Ground Wires Found When Installing Tail Light
    First, go ahead and follow the instructions and ground the light to the frame. After this is done, I would suggest grounding the other wires to the frame as well since you don't exactly know what they are coming from or what they are for. This is a safe bet and will prevent you from running into any issues.
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  • Wishbone Trailer Wiring Harness for a Magic Tilt Boat Trailer
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