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

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

Item # A35W42B
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Optronics Wiring - A35W42B
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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 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 800-298-1624 for expert service.
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Optronics 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


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

Alternate part number: A-35W42B




California residents: click here



Customer Reviews

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

Average Customer Rating:  4.9 out of 5 stars   (570 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.

- A35W42B
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.



- A35W42B
by:

I purchased this to update my very old and non-functioning pontoon trailer wiring. I needed the extra length and was glad etrailer provided it as an option. Since the new wiring harness was already set up to run each side separately, it made easy work of rewiring the trailer. I really like etrailer products. I think they are of good quality for a good price. Sorry, no photos of the job.


Comments
Working like a charm. Still happy with the product and the outcome.
Lauri - 05/18/2021


- A35W42B
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.



- A35W42B
by:

Good quality products, and very fast shipping. I have trusted e-trailer with past purchases as well. This order included led tail lights and wire harness for my pontoon trailer. I needed a 35 foot harness and e-trailer had it. They are very difficult to find. And the lights and wiring was first class. Also e-trailer provides good videos for product instructions. Great company.


Comments
Trailer lights are working great. Being led and submersible is just what I need.
Steve - 10/09/2020


- A35W42B
by:

Wires installed easy and worked for a couple of months. After getting the boat ready this spring I noticed that despite using watertight shrink wrapped and liquid electrical tape sealed connections the wires had completely corroded and now need to rewire the trailer all over again.



- A35W42B
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!!!!



- A35W42B
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!


Comments
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



- A35W42B
by:

Good price reasonable quality This wiring harness has worked well since I installed it about an year ago



- A35W42B
by:

Works great. Had to lengthen the ground wire about 2 feet to fit through the length of the trailer tongue; but when fully installed, all the lights including side lights worked.


Comments
Still working great.
Raymond M - 01/11/2021


- A35W42B
by:

As usual etrailer bales me out. I had a hard time finding a light kit with a 35 ft harness. etrailer had a harness for a great price and if course great customer service to go with it.



- A35W42B
by:

So far everything is working great. The lights are much brighter than what I was expecting. Everything was installed on my boat trailer.



- A35W42B
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!



- A35W42B
by:

I had a 16foot flat trailer that had multiple broken wires and a defective flat plug with a broken ground (white) wire. I decided to completely rewire the trailer and add a couple of lights on each side near both fenders and a 3 light row on the back. The trailer is about 19 feet long counting the tongue. This harness was perfect! The wires were plenty long enough and split to go down both sides of the trailer and wire new lights on both sides and the rear (including new brake lights/turn signal lights). I was a complete novice at this but the etrailer website videos and explanations completely enabled me to do it myself.



- A35W42B
by:

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.



- A35W42B
by:

Great service, the mail was a little slow in delivering the product but no fault to etrailer. Will order again



- A35W42B
by:

Exactly what I ordered. Worked perfectly for my boat trailer!! Thanks so much!



- A35W42B
by:

worked great to rewire our trailer



- A35W42B
by:

After chasing gremlins for one whole summer, I decided just to buy a new harness. This harness was just what I needed. Now all of my lights work and I couldn't be happier.



- A35W42B
by:

Real quick shipping.



- A35W42B
by:

Project is ongoing. I ran both harnesses. Together they will light the tiny home. It is 98% finished. I had a 10 month setback. I'm a critical care charge nurse. Covid took me out. I've just gone back to work. Now painting. Next, flooring.



- A35W42B
by:

Makes rewriting trailer very easy Shipping is fast and price is good



- A35W42B
by:

Easy install, nice quality set up.



- A35W42B
by:

Appears to be a much more durable wire than what I pulled off of the trailer I was replacing this with. (24 ft Pontoon Boat Trailer). Old wire had corroded and just snapped, but this feels much better and is a thicker wire and insulation than what was on it.



- A35W42B
by:

Great 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.


Comments
Everything is fine and I want to thank you for your fine service. The trailer is working very hard for the family.
Fred C - 07/09/2015



- A35W42B
by:

The product is good quality and works fine. What I don’t understand is why it takes so long to ship and receive your order. I placed the order on the 12th, it didn’t ship until the 16th and I received it on the 19th.


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Ask the Experts about this Optronics Wiring

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    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...
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