Videos are provided As a guide only. Refer To manufacturer
installation instructions And specs For complete information.
Item # 38955
Orders above $99 qualify for free shipping
Shipping Weight: 1.52 lbs
Allows motorhome or R.V. to power the lights on the towed vehicle without power feedback.
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.
Video of Tail Light Isolating Diode System with Wiring Harness
Videos are provided As a guide only. Refer To manufacturer
installation instructions And specs For complete information.
This part is for a vehicle to vehicle towing kit. What this basically does is, say you have an RV or motor home or pickup truck and youre going to towing another vehicle on all four wheels youre going to need this wiring harness to make the lights on the towed vehicle work with the towing vehicle. Well start by showing you the different components of this kit, its really pretty simple if you break it down. First the connection here is a traditional four pole flat. So you have your four basic signals, your ground, running lights, left turn and right turn. You also have plenty of harness to attach this on the towed vehicle. When you make your connections on the towed vehicle itself, you have to install these diodes here. At the point where you make your connections on your vehicle whether it be your left or right turn or the running light circuit you will have to install these diodes.
To give you a couple of quick notes about these, what happens is they do go in a specific direction in the wiring harness. to keep it simple basically the single prong here is listed as out, that goes onto the taillight itself out to the bulb. Then you get the two inputs here, one of the inputs is going to be the wire you just cut because youre going to splice this in between the two. It does not matter which one, the wire is going to come in one side and out the other. This other pin here is going to provide input from your trailer harness coming from the towing vehicle itself. So for instance you would take your green wire here and run it to the other open end and it will go out and power your taillight being towed down the road by the RV. As you can see theres 4 diodes and theres a reason for that. Theres going to be one for the left and right turns, and both turn signals are going to have there accompanying running lights. So youre going to need a diode for each of the running lights. Now weve opened up a small bag of parts which contains all the spade connectors needed to do the install. Basically what these are, you cut your wire that you need and you splice the wire back and expose about a quarter inch or so of it and these get crimped on. Be sure you have the right tool to do that with because it makes all the difference in the world with a tight connection and loose connection. Once you do that, it just slides onto the diode prong itself. You may also want to invest in some dielectric grease that will protect it and keep things out that would cause corrosion which would eventually cause an open circuit. As one final note you may want to take into account, if your towed vehicle has the same turn signal and brake light bulb, this kit is for you. If you have separate stop lights and turn signals, say for example your turn signals are amber that means theres going to be a different box to achieve that so you have your separate turn signals and stop lights still the same. That covers part # 38955.
Average Customer Rating: 4.7 out of 5 stars (115 Customer Reviews)Allows motorhome or R.V. to power the lights on the towed vehicle without power feedback.
by: Charles S.07/09/2013
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! :) 88444
by: Sandy Snowden03/02/2015
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. 176567
by: Dave H.03/31/2014
Arrived super quick, even with standard shipping. Product looks just like the pictures. Haven't installed yet. 122987
by: Bill Springer11/21/2012
Got the kit installed. Using on my toad (RAM Dakota) to be pulled behind my motorhome. My first one like this and easy and good quality product. Highly recommend. 59891
by: David E. Adams Wi.08/29/2016
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. 288894
by: linwood m08/28/2011
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. 22966
Perfect product for wiring our Miata as a toad for the RV 220698
by: Herbert P04/04/2014
Great product, worked good and easy to install. Thanks for the fast service. 123723
exactly what i ordered. 69708
by: Allan A.11/17/2011
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. 27067
by: Joe G11/22/2011
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. 27314
by: Ron Waldo02/20/2017
My experience with etrailer was great. From the beginning giving my order to Delisa, whom was cordial, comical and extremely helpful right on thru the shipping. Everything went as Delisa said it would, smoothly. The installation was easy after I got my RV lights corrected but that is not etrailers fault. The wiring I bought for my truck was perfect. I recommend etrailer.com to everyone and a big THANK YOU to DELISA.....Ron Waldo 343574
by: Paul P11/04/2013
The delivery was prompt and the packaging was excellent. The product is exactly like the picture. I would recommend this site to all that are shopping for this product. The only reason that I gave the product a 4 star vs a 5 star is that the plug that hangs in front of your vehicle does not have a cover to protect it from corrosion. What you see is exactly what you get. I would buy from this dealer again. 106166
by: David B10/25/2013
Product contains everything a do-it-yourself handyman requires to completely wire a vehicle's existing lights for towing. The rate limiting part of this project is deciding how and where to run the wires from the front of the vehicle to the tail lights. The actual wiring of the lights requires about 15-20 minutes. Now I don't have to use the magnetic tow lights and string the wire through the vehicle. Thank you. 105205
by: Tom B01/27/2017
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. 335893
The product arrived as promised and all components seem of good quality. I was apparently shorted, I don't think I dropped or lost it, one spade lug which required an extra trip to the hardware store. It would be nice if a couple of extra lugs were included incase one gets lost or messed up during install. Other than that, all worked fine as promised after install. 67591
by: Bruce L08/10/2015
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. 218291
The product is now installed and works great. The instructions were sketchy (they were literally a sketch!) but I was able to muddle through it. Instructions did not call for the signal light wires to actually connect to the (separate) signal lights which I have on my Geo Tracker. When I rewired it this way everything worked fine. 67929
by: Earl Cook01/24/2012
The product arrived in three days in very good condition. Installation went well, the video is a great help. I suggest that a longer ground wire be installed. I was required to add some length to it to make compatible with roadmaster tow bar to my motorhome. All in all a good product. Earl Cook 30239
by: John B06/13/2013
Everything I needed was included in the kit. An online video showed the installation steps very clearly. The wire provided was long enough for any vehicle. I had 6-8ft leftover after installation in my Dakota quad cab truck. Experience level: Above average (retired engineer) 84390
My order arrived earlier than expected which was a plus, started the install followed directions and ready to Tow in no time. The hardest part of the whole process was deciding which route to run those wires. Great product however delivery and customer service a plus 207952
by: James B.06/11/2012
Delivery was prompt and product performs as advertised. The only difficulty was with the crimp-on spade terminals which are too large for the harness wire. It was necessary to solder the cable ends to make them slightly larger to get a tight crimped connection. 43688
The order shipped very fast. I installed the wiring kit with not problems. I liked having 35 ft of wire, it gives you lots of choice of where to run the wire. The kit I got has 2 brown wires for park lights so I did not have to run a jumper. 149090
by: Steve k06/08/2015
View of hook up trial 201552
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. 344216
by: Walt H.12/14/2016
I have gotten several products for your company and have been extremely happy with everything. In the future if I need anything I would definitely make more purchases and your customer service is excellent. 324912
by: Bill Springer08/05/2015
I am a returning customer and have this same product installed but I bought this for a friend trying to help him set up a toad for running behind his motorhome. Highly recommend; always fast and efficient 216969
Good product. Fast shipping. Components were sent as described. A quick install guide shipped with the product would have been helpful. Had to go back and search online for install instructions. 29790
This is the second time I've purchased this product. Very good deal. It is supported with plenty of videos and instructions for installation. If I get another dingy vehicle, I'll buy it again. 214038
Got my tail light kit, very pleased with the quality. Install was easy because everything you need is provided, except tools, works great! Price was also the cheapest I found on line. 311566
by: Marshall J02/15/2016
Checked out the package and it is all there and packaged nicely. Received it very quickly and appears to be as advertised. Haven't installed it yet, but will get a round to it soon. 237824
by: Larry M.02/03/2014
Ordered this diode harness and was surprised how fast it was shipped. Instructions are easy to understand and should be installed without problems. It will solve my tow car lighting. 115552
by: Doug S.07/08/2011
The ground wire is way too short. I had to add afew feet to it. This product is used by RV'ers and the towed car is going to be at least 5 feet behind the motorhome connection point. 18949
by: Bernie K06/28/2014
Easy to order and quick shipment. Items received as specified in the online product description. Thank you for the detailed installation instruction that i got from your website. 138139
by: Mark W.12/20/2013
My order was processed and in the mail with great speed,when it arrived it was just as pictured with good clear instructions.I am very pleased and would recommend them to everyone. 110727
I havn't installed or used the product but the service was EXCELLENT! It was shipped the day it was ordered and delivered two days later, great service for the Christmas season. 110688
by: Gene F05/30/2011
Tow bar brakets were correct ones and in excellent condition. They were delivered on time. I have ordered from E Trailer three times; each time have been completely satisfied. 15686
by: Ronj S10/07/2013
On-line instructions were perfect. Installation a breeze. Only suggestion I have is to include a couple of extra connectors in the package. Raise the price a buck if need be. 102860
by: Gene T.02/29/2012
Product was exactly as advertised. Pictures were exact representative of the wiring system. Delivery was reasonably prompt. Will definitely be a returning customer. thanks 32800
I used this kit to wire 1987 Jeep Wrangler for towing behind my motorhome! It worked perfectly and was relatively easy to install! I am very pleased with the product. 171938
by: Brett M.05/20/2015
Great product. As other have said the ground wire is way to short. I had to add 4-ft to mine. I did still recommend it to my dad and would buy again for another car. 194635
by: Donavon K.12/10/2014
It was excellent and all the quality I would expect. Shipping was also fast and efficient and this is my second order and I have been pleased in both orders. 164110
This product was super easy to install, my total installation time was about 2.5 hours on my Explorer Sport Trac. you won't find a better product or price. 152731
The products were exactly what I needed and were of a very good quality. The service was fast and hassle free. I would recommend this business to anyone. 68899
by: chuck s10/29/2012
Easy install. Good instructions, plenty of wire length for my application (Mazda Miata). Worked perfectly first try and we are pleased with the result. 58349
Excellent product - better than the product was the professional support and help. These people take support seriously. would recommend to anyone. 38130
by: jim p.02/05/2016
exactly what I wanted. shipped and arrived quickly. wonderful service. I would recommend customers to purchase from this company. I am a happy man 237015
by: Tom G08/06/2013
Everything I ordered was received and packed extremely well. Great service and the product is what was advertised. Thai you so much! Tom G 93566
by: Rick Breitenbach10/12/2015
I am setting up my pick up to pull behind my motorhome. Etrailer was very helpful. I purchased what I needed and the product arrived fast. 229761
by: John C06/23/2012
The diodes and wiring harness that you sent me were just as discribe and just what I needed. Thank you very much for your promped service. 45378
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