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  1. Tow Bar Wiring
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  4. Splices into Vehicle Wiring
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  6. Tail Light Mount
Tail Light Isolating Diode System with Wiring Harness

Tail Light Isolating Diode System with Wiring Harness

Item # 38955
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Our Price: $35.60
Tow Bar Wiring
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Shipping Weight: 1.46 lbs
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Hopkins Universal Tow Bar Wiring - 38955
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Allows motorhome or R.V. to power the lights on the towed vehicle without power feedback. Lowest Prices for the best tow bar wiring from Hopkins. Tail Light Isolating Diode System with Wiring Harness part number 38955 can be ordered online at etrailer.com or call 1-636-306-4830 for expert service.
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  • Reviews (170)
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  • Why etrailer?

Hopkins Tow Bar Wiring - 38955

  • Diode Kit
  • Splices into Vehicle Wiring
  • Universal
  • Tail Light Mount
  • Hopkins

Allows motorhome or R.V. to power the lights on the towed vehicle without power feedback.


Features:

  • Includes 4-pole flat trailer connector.
  • Max amperage per diode: 3 amps
  • Max voltage: 24 volts
  • Wire lead: 35' long
    • White ground wire measures 42" long.
  • Wire configuration:
    • Brown: Left and right side running lights
    • Green: Right side turn and brake lights
    • Yellow: Left side turn and brake lights
    • White: Ground


31821

Please note - 3 wire system on towed vehicle: If the towing vehicle has a 3 wire system, where the brake signal is sent along a separate wire from the turn signals, then a wiring converter (118158) and 2 additional diodes are needed to retain separate amber turn signals. If you only use this diode kit (38955), then the vehicle brake lights will function as brake and turn lights.




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38955 Tail Light Isolating Diode System with Wiring Harness






Customer Reviews

Tail Light Isolating Diode System with Wiring Harness - 38955

Average Customer Rating:  4.8 out of 5 stars   (170 Customer Reviews)

Allows motorhome or R.V. to power the lights on the towed vehicle without power feedback.

by:

I was looking for something to add to my 2014 Equinox for tail/brake/t-signal lighting for towing behind my motorhome. This system worked perfectly , and couldn't have been easier to install. The hardest part was running the wiring from front to rear ( through frame rails and what-not ). Tail-lite hook-up was a breeze. There was plenty of wire to do the job also. Now the vehicle lites work as a trailer and does not interfere with the normal vehicle lite operation.




by:

No female spade connectors come with the kit but sure got a lot of 4 wire cable and flat 4 pin connector.




by:

installed your isolating diode wiring harness 38955 also the blue ox base plate bx1126 . install was very easy with video on your site.was installed on my 2007 wangler to be towed with holiday rambler motor home.




by:

Plenty of wire. Great directions.




by:

Very good quality and was easy to install by the directions.


Comments
Excellent I Could not be happier with it!!
Roger B - 12/23/2021


by:

Installed the wiring kit on my 2008 Smart car. The Diode pack was exactly what I needed and made the installation simple and very clean. The kit was 100% complete in every way with more than enough wire to do the job. Thanks for a great product and at a price that made it practical.




by:

The weekend after receiving your Diode Kit, I went to work on my wife’s 2015 Trax. The hardest part of the whole project was running the harness from the engine compartment to the tail lights. The first thing I did was to attach the ground lead (white) to the negative terminal of the battery (it has a small bolt next to the main terminal for this purpose). After that, it was very easy to hook-up the diodes with the hardware included. The Trax actually has four separate lights, turn signal, brake, backup and running lights. I chose the light which had three wires going to it (red, green and black). One of the wires went to the running light filament, and one went to a brake light filament. The black wire was a ground, which I did not need. After the wiring was complete, this one light served as running, turn and brake. I secured them within the tail light assembly with duct tape and the project was finished.
After connecting the trailer, everything worked perfectly. I’m very pleased with this product.
Sandy Snowden, Katy, Tx.




by:

Good to deal with




by:

The product arrived as expected & on time, with plenty of instructions and even a measure of product installation “Difficulty Rating”. I diffidently would use this measure to determine if I need help or could do it myself.

Thanks for your excellent response time and “World Class Customer Service”.
A.A.




by:

This is exactly what I needed to complete my tow package for the RV. I have seen for several years RVs towing a toad and always liked the idea of having the toad vehicle tail lights work from the RV. The diodes were easy to install and the spades fit tight. Instructions were clear even fo rthis old guy. Delivery was spot on with several emails communicating to me what was going on with the order. Thanks a bunch! :)


Comments
It has been a year and after returning from vacation after the 4th I am very pleased to express my satisfaction with the diodes I installed on my Jeep wrangler. I get asked all the time how I was able to get the tail lights to come on while towing. I am always eager to tell and show everyone. What a great product. Still working GREAT!
Charles S - 07/09/2014


by:

The wiring harness worked well and connected as it was mad to do.




by:

A great set that could only be improved on if it had six diodes.


Comments
No problems so far
Peter - 10/11/2021


by:

Haven't installed the product yet- can't understand the instructions & diagram. When Hopkins having their products made in Mexico- it hurts US workers and hurts US consumers also ! I've purchased a product that I can't install, due to the vague instructions & diagram. I would appreciate it , if you would send me something that I can understand. JR


Comments
I see that you are installing this kit on a 2015 Kia Soul. I have a attached a video of an installation of a diode kit on a 2015 Kia Soul. The video is for a part number that includes a coiled cable but it is the same install for the hopkins part # 38955.
-- Etrailer Expert Heather A - 11/13/2018


by:

Kit arrived on time and in good condition. Installation instructions were accurate, routing of wires was most difficult part of install as expected. Product has been working as advertised since installed. Thank You!




by:

The wiring kit is great. After 6months the plug holder is loose and when you go to plug it in it falls in. I siliconed it back in place and it is staying so far. Other than that it is a great kit.




by:

I got everything I needed to wire my Ford Ranger to be able to pull it behind my RV. The instructions were simple so I had no problem installing. It's saved me a great deal of money by being able to do it myself.




by:

This towed car wiring kit is excellent for the do-it-yourself RV owner in that it includes everything required to wire the rear lights yourself. It is reasonably priced and made up of high quality components.

I strongly recommend etrailer for all of your tow bar, bracket, wiring and accessory purchases. They are responsive, knowledgeable, and carry everything you should need.




by:

Ordered on line price was good, delivery was quick, install went great thanks to YouTube video (2011 Equinox). Have towed it approximately 2000 miles using road master falcon 2 tow bar, and all parts are working well.




by:

Exactly what I needed to hook up my tow lights on my we 2001 jeep grand Cherokee limited. This kit makes it fast and easy.


Comments
Still working great
Tim - 03/09/2019



by:

The installation of these wires were straight forward and easy to complete. After 1 year of use the system is still working perfectly! Highly recommended product to enable towed vehicles turn and brake lights vice separate set of lights. Set up once and no further action required.




by:

Worked great!




by:

I installed the product on a 2012 Chev Cruze. Very easy to do and only took a couple of hours. Lights work as expected with no surprises. Would recommend to others.




by:

Service is top notch. Especially Sarah !!!! Ran into a issue with someone altering OEM on current tow set up and Sarah was able to trouble shoot over the phone and sent me what I needed. Etrailer has had my business and will continue to get it. I’m using the Demco Commander tow bar and base plate on a 2017 GMC 3500. Pulling with a Damon motor home.




by:

I wish they would have included a few extra terminals. Those things tend to break or get lost in the process, so a few more would have been nice. Instructions in the package were mostly useless, but there is plenty of documentation on the website listing.




by:

This Is the basic toad wiring kit that will allow you to use the toad's taillights in conjunction with your motorhome. It comes with a "Four Flat" plug but can cut and attatched to any plug you need. Complexity of installation depends on your toad. My Jeep Wrangler was easy to wire. My Subaru Impreza was far more difficult do to its design.



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