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

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

Item # A40W5B
Our Price: $40.03
Trailer Wiring
Shipping Weight: 1.38 lbs
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40 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire 5 Flat A40W5B
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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. 40 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire part number A40W5B can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Wiring - A40W5B

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

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.


Features:

  • 5-Way trailer harness connects to your tow vehicle to control trailer light functions
    • Ideal for marine trailers with hydraulic or surge brakes
  • 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
  • Auxiliary wire (blue) connects to backup light circuit to disengage surge brakes when you are driving in reverse
    • Hydraulic actuator must have electric lockout feature built-in to disengage the trailer brakes
  • Color coded wires help with installation
    • White - ground
    • Brown - tail lights
    • Yellow - driver side stop/turn
    • Green - passenger side stop/turn
    • Blue - auxiliary wire


Specs:

  • Wire harness length: 40'
  • Ground wire length: 30"
  • Auxiliary wire length: 5'


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

  • Truck Lite # 002295


A40W5B Optronics 40 ft. Wishbone 5-Way Trailer Harness with 30" Ground and 5 ft. Blue Wire

Alternate part number: A-40W5B




California residents: click here


Customer Satisfaction Score:


Customer Reviews

40 Ft 5-Way Trailer Wiring Harness - Wishbone Style - 30" Ground - 5' Auxiliary Wire - A40W5B

Average Customer Rating:  4.8 out of 5 stars   (143 Customer 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:

My boat trailer had a split wiring harness that had suffered over the years. I purchased this harness for the boat trailer and with attaching it to the old wire was able to pull it through the frame and connect all new lights in an afternoon.



by:

Fast n easy!! Exactly what I needed.



by:

Great Quality. This harness has 20ga wire. wish the wire gauge was thicker. I used this for a boat trailer rewire and 16ga would beef the harness up perfectly.



by:

This harness worked well for my 21 foot boat trailer. There was excess wire and it took care of some corrosion problems I had with my old wiring.
Etrailer always has great descriptions so you know what is being shipped.



by:

Easy installation



by:

Product is quality and order came oerfe ctly



by:

Just what I was looking for. I believe this is going to work as I run the wire from the front of my 5th Wheel to the back.

John B.

12/9/2014

It is working out fine. Thanks Etrailer.



by:

The harness seems fine but receiving this item from etrailer was terrible. I didn’t have enough in my cart for free shipping so I was charged, which is fine. What I am not fine with is etrailer using the pony express to get it to me. If I can find it on [online vendor] I will get it from there.



by:

I guess I should of read discription better , wire harness delivered had 4 wires that were 30’ in length , but the blue and white wires were only 36” in length , I had to go out and but a roll of white and a roll of blue to complete replacement PU camper break circuits.

Etrailer Expert

Jenny N.

1/31/2022

This harness comes with 40 foot of the brown, yellow, and green whites. It comes with 30 foot of the white ground wire and 5 foot of the blue auxiliary wire. The auxiliary wire connects to backup light circuit to disengage surge brakes when you are driving in reverse. The hydraulic actuator must have electric lockout feature built-in to disengage the trailer brakes



by:

Etrailer is awesome
Great website for
detailed parts
I buy from etrailer all the time

Jim M.

5/10/2018

Great etrailer is awesome



by:

Wry impressed with how quick the items came. I ordered some other items the day later and still waiting for them but overall very happy.



by:

THE PRODUCT CAME QUICK AND ETRAIER AS THE ONLY PLACE TO HAVE THIS PRODUCT. 40 FT TRAILER HARNESS . WE WILL BE INSTALLING IT ON MY 2010 CONTINENTAL BOAT TRAILER . FILMING IT ON MY YOUTUBE CHANNEL . .SHALLOWHOOKERFISHING.COM . ILL BE HAPPY TO MENTION ETRAILERS.COM ON MY CHANNEL. .



by:

I got my 40ft wishbone trailer harness in about 5 days. Was held up a day because of the Christmas holiday. All in all I was quite satisfied with my purchase. I'm putting "Pole Lights" on my trailer to keep them out of the water. I didn't want to "splice any wires", so I ordered the 40ft length. I have not yet installed this, but plan to start today. Its been a very busy holiday season, and now time to get to work.

Capt. Jim Hedgecock



by:

Last Fall I ran new trailer wiring for my boat trailer. This wiring was great for the application and trailer lights work great today.



by:

Design wise it is excellent, the wishbone design is intelligent and makes rewiring a boat trailer simple and clean.

The Good rating? The wire gauge looks to be 18-20, wish it was heavier gauge, especially since it is a 40 ft long harness. And it is made in China or Taiwan, not a heavy duty or perfect construction.

If it lasts as long as my original, 14-years, I'll come back and bump up my rating, and I bet you can't find a better one.

As far as the transaction, it was excellent, had the 40 footer I needed, great price and super fast shipping.



by:

Great product



by:

etrailer is a the only place I could find this item as I live in a rural area. The harness was perfect and did the job well. Service and shipping time was perfect.



by:

Very satisfied with product. Only recommendation is charge an extra minimal amount for splices, terminals and etc.
In my DIY application, replacing the bumper plug connector. I'll retain the remaining wiring harness for near future replacement.



by:

Rep knew what I needed and did a great job of selecting and sending the item to me. I recommend these folks very highly



by:

nice wire and plug setup. Its better to change the whole wiring harness if the wire is getting stiff.



by:

Product was shipped quickly and matched the product description. Tried to find it locally for a price comparison but nobody stocked this item. Shopped online and etrailer.com had the best price. Good product, good service. Thank you.



by:

My 5 pin, 40' wire harness arrived within just a couple days. Excellent price and Excellent service. Thank you etrailer.com.



by:

Completely rewired my trailer and this kit had all that I needed.



by:

Great company to deal with. Very prompt getting my product to me. Also, the kept me continuously updated on when I would receive it. I would highly recommend etrailer.



by:

Very pleased with my 40’ 5 pin trailer harness. Highly recommend these guys!


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See what our Experts say about this Optronics Trailer Wiring

  • Wire Gauge Size of the 40 Ft 5-Way Trailer Wiring Harness A40W5B
    The 40 Ft 5-Way Trailer Wiring Harness part # A40W5B uses 20 gauge wire according to Optronics. This is pretty standard and will work for the vast majority of trailers without issue.
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  • What Wire Does The Yellow Wire With Brown Stripe On My Trailer Connect To
    On the trailer's 5-way connector the yellow wire with brown stripe is most likely a running light circuit but you want to be sure. There is sometimes a yellow/brown wire which is ran down the left side of the trailer for tail lights and a green/brown wire which is ran down the right side of the trailer for tail lights. Since wire color functions may vary depending on the manufacturer you still want to test the wire to determine the function by using a vehicle battery and jumper wire on...
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  • Why Does Wishbone Trailer Wiring Harness A40W5B Have Extra Brown Wire
    I could not find etrailer order history for you based on either your last name or your email address so I do not know which vehicle wiring harness you have. The linked page shows the 4-pole trailer wiring kits we offer for your 2008 Nissan Sentra. This is the only type of wiring kit we have for this vehicle. Some trailer wiring kits will use dual running light wires to avoid the need to splice and run that circuit's wire across the sides of the trailer. These are called wishbone harnesses...
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  • Where Does Blue Wire of Trailer Wiring 5-Way Normally Run to on Trailer
    So the blue wire of the 5-ways like the # A40W5B normally runs to the reverse lockout solenoid of a surge brake actuator like what you described having. The blue wire on the vehicle side of the wiring runs to the reverse light circuit. This allows the solenoid to have voltage when the vehicle is put in reverse preventing the brakes from applying. This runs right to the back of the actuator on the trailer coupler which is why you don't see the wiring ran to the back of the trailer.
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    Typically there is a white, green, brown, Yellow/Green and brown, and a yellow wire so since you do not have a dedicated yellow wire you will need to test wire functions by using connecting the brown, green, yellow/brown, and green brown one at a time to the positive terminal of a battery while grounding the white wire and seeing which functions come on with each wire. Since the colors on your old connector are not standard you will need to make the connections by function and not the color...
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  • Trailer Wiring Harness With Tinned Wire
    While tinned wiring is the norm when it comes to interior wiring on boats, boat trailers see a minimal amount of water compared to the actual boats. They do use a tin coating on the pins that are the parts of a wiring harness like the Wesbar 5-Pole Flat Connector # A40W5B since those are most exposed to moisture, but since the actual wiring is rarely exposed to water I'm guessing that's why they don't go the extra mile when it comes to using that wiring within the harnesses. As far as...
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  • Wishbone Trailer Wiring Harness for a Magic Tilt Boat Trailer
    I believe you have what is referred to as a wishbone wiring harness. A wishbone wiring harness has 6 wires and is the same as a 4-way for the exception that it has both running light wires ran to the trailer connectors as opposed to splicing them together and then running them to the trailer connector. The functions should be as follows: Green - Right Turn/Brake Yellow - Left Turn/Brake Yellow/Brown - Left Running Light Green/Brown - Right Running Light White - Ground Red - Reverse Lockout...
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  • Recommendation to Replace Trailer 5-Way That Has 9 Wires
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  • Available 5-Flat Wishbone-Type Trailer Connectors
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  • Wiring Needed to Connect Surge Brake Reverse Lockout to Trailer Wiring
    Not every boat trailer will have the reverse light circuit completed so you'll just need to complete this circuit. Most likely you have a 4-way now so you'd want to swap that out to a 5-way and run the 5th circuit to the reverse lock out solenoid. For that we have the part # A40W5B. The other wire of the solenoid will need to ground to the trailer frame.
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  • Replacing 5-Way on Trailer that Used 8 Wires
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  • Replacement Trailer Side Wiring Harness for a 1996 Yacht Club PWC Trailer
    Trailer side wiring harnesses are not specific to the trailer so you can use any one that has the proper connector and length for your 1996 Yacht Club PWC trailer. I have included a link to the trailer side harnesses for you. If your trailer has a 4-Way flat connector a popular option is wishbone harness # A35W42B. A wishbone harness has 2 wires connected to the running light pin so you won't have to run jumper wires from one side of the trailer to the other for running lights. If your...
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Do you have a question about this Trailer Wiring?


Info for this part was:

Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Brian T
Updated by:
Brian T

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