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35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground
Special Savings On Select Optronics Wire Harnesses.

35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground

Item # A35W42B
Retail:$25.47
Our Price: $20.96
You Save: 18%
Trailer Wiring
Shipping Weight: 1.19 lbs
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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. Great Prices for the best trailer wiring from Optronics. 35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground part number A35W42B can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Wiring - A35W42B

  • Trailer Connectors
  • Trailer End Connector
  • 4 Flat
  • Plug and Lead
  • 31 Feet and Longer
  • Optronics

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


Features:

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


Specs:

  • Wire harness length: 35'
  • Ground wire length: 42"
  • 3-Year Warranty


Manufacturer Cross Reference
Harness will work as an exact replacement for:

  • Truck Lite # 108835
Wishbone Wiring Diagram


A35W42B Optronics 35 ft. Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire

Alternate part number: A-35W42B




California residents: click here


Customer Satisfaction Score:


Customer Reviews

35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground - A35W42B

Average Customer Rating:  4.8 out of 5 stars   (739 Customer Reviews)

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

by:

2 things. 1st@: I think there should be an option to pick tinned wire. 2nd: The ring terminal for the ground needs to be bigger.



by:

Worked out great. Direct replacement for my old 4-way boat trailer harness that had corrosion damage at a quick splice joint causing my trailer marker lights to not work. Easy to follow wiring diagram from etrailer store page.



by:

Great product very easy to install my order arrived 3 days early I received emails so I was informed when my wiring harness was shipped and one when it was delivered Thanks E Trailer A happy customer!!!



by:

A quality wiring harness, plenty long enough for my boat trailer.



by:

1 year, and so far so good. I have had cheap harnesses before that would oxidise from the inside out and break when connecting flat 4, but this one is doing fine.



by:

Good wishbone wiring harness, decent ground eyelet, not tiny



by:

Replaced the wiring and lights on my 1992 boat trailer. I was able to get everything needed from etrailer. I think Optronics is of the highest quality
and recommend both etrailer and Optronics product.



by:

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.



by:

The white wire needed to be a bit longer, but I made it work, other than that a



by:

The wiring harness arrived quickly and was installed with ease.



by:

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!

Eric

1/29/2019

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.



by:

I am giving this item an Excellent review based on my former (very positive) experience with your products, but actually I haven't used it yet. My former harness is still working. I will use this as a replacement when the time comes.



by:

Perfect! 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!!!!



by:

High quality, fairly priced, totally sa tisfied!



by:

This harness is exactly what you expect to receive when you order it.



by:

Item was exactly as described and just what I needed to rewire my trailer. I also appreciate the great customer service as I was emailed instructions to aid me in the installation of the item ordered.



by:

This worked great, had to rewire my trailer after having it painted and reconfigured and this item was long enough and allowed me to tie in my additional lights.



by:

When it was time to rewire our 2007 boat trailer I selected the wiring harness from etrailer because of its wishbone configuration, long ground wire and quality. We used an electrical fishing tape to pull the wire through the channels of the trailer and it was straight forward and relatively easy. It has worked just fine and we have no complaints. Great price and fast service too.



by:

A basic wiring harness, meets its purpose very well. Arrived on time.



by:

This harness has a heavier gawg than the box store brands. Rseems to be good quality.



by:

Rewired trailer lights. Solid product. After 1 year no issues noted.



by:

Absolutely Fabulous! Exactly what I was looking for but couldn't find at any retail store in my area! The wishbone design splits the brown wire at the plug. Makes wiring both sides of the trailer with no splices or having to find additional brown wire sold by the foot!



by:

Exactly what I needed to rewrire my boat trailer. Received sooner than expected as well.



by:

Very pleased with products and service . Both items I purchased for my new trailer I built. I needed a coupler that would fit into the 4x4x1/4 in tubing and etrailer came thru with a perfect fit at a great price. My trailer is 28’ long so the standard 25’ harness oils not work. Again etrailer came thru with a 35’ harness which is what I needed. Both these items were shipped quickly and at a great price.



by:

Typical style wire. Not that you really need it but no diagram came with the wiring as it shows on the website. Would be helpful tho

Etrailer Expert

Katrina B.

5/17/2023

This harness is a wishbone style, which is where the browngreen wire for the running lights are on the right side and for the left side running lights, a yellowbrown wire. The yellow wire is for the turn signal and brake lights on the left side. The green wire is for the right side turn signal and brake lights. Finally, the white wire is for ground. I will email you the wiring diagram so that you have a better visual.


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See what our Experts say about this Optronics Trailer Wiring

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