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Used when a motorhome with a 2-wire system is towing another vehicle with a 3-wire system, by way of a tow bar.
Features:
Note: You will need to install a tail light isolating diode system (38955) and 2 additional diodes (RM-792) with this tail light converter to prevent electrical feedback when flat towing a vehicle. Vehicles with separate turn signals and brake lights will need a total of 6 diodes.
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Average Customer Rating: 4.8 out of 5 stars (118 Customer Reviews)
Used when a motorhome with a 2-wire system is towing another vehicle with a 3-wire system, by way of a tow bar.
The "Vehicle To Vehicle Tail Light Converter", Item #118158 is serving my needs well. I refitted my trailer completely using all LED lights. I mounted the converter inside the "C" channel underneath my tongue mounted toolbox for a little added protection. I also soldered all connections throughout the re-wire and used heat shrink &/or liquid rubber over all connections. I feel that proper planning prevents poor performance. I ordered numerous lights from etrailer also, and all are working fine. When I chose to call them with a question about one of their products, it was answered quickly and appropriately. I am a business person, and that's customer service!
Jim R - 04/06/2021This product works well with some thought and acknowledgement that it has limitations. I have just bought my second one. The previous one failed after five years. This new one etrailer recommend the use of diodes to prevent feedback to the towing vehicle. This is not a bad idea but was not previously available. The circuit diagram that comes with this unit was misleading to me. Eventually I figured it out and will passon what I learned. My trailer has separate orange indicators. It is wired as all my trailers are with a seven way plug. You will see each diode having three connections. Two from the towing vehicle and one to the indicator bulbs. I just used one of the diode input tags connected to the appropriate wire from the seven way. The output I fed to the indicator bulbs. I have three indicators on each side of the trailer and they can all run off of the same tab. I am enclosing a few pictures. The first one is the old unit which was housed in a separate box screwed to the chassis. Then I had a second box which held all the connections. The second picture shows the new unit contained in its own box with the five diodes used. The box is just a plastic project box from Radio Shack. The last picture is of the finished unit all sealed and ready to go. Now for those limitations. Do not expect this to work as though it were an extension of a four wire vehicle. The indicators will work and the brake lights work BUT the indicators go off when the brake is applied. The unit cannot run the separate indicator and the brake at the same time.
I gave up trying to find a wire to tap for a third brake light on a 2013 GMC Sierra, so I ordered a 2 to 3 wire adapter ( #118158) as recommended by you expert Michael H. He stated that only one of the inputs was needed, but both Left and Right turn were required to make mine work at all. That aside, the product was received quickly and installation was simple using the enclosed diagrams. I have never seen anything mentioned anywhere about waterproofing undervehicle connections. I do and they last for years.
I have used etrailer many times and have always been satisfied. If you need parts for campers, towing, etc., this is the place to go.
I installed a European 13pin receiver on a 2018 Ford Explorer and stowed the wiring adapter under the vehicle. Worked flawlessly so far with caravans and bike carriers.
Christian G - 03/01/2021This converter worked great for what I intended it for. I was wanting to add a third brake light to back of my fifth wheel trailer. I purchased STL179RB Glolight Thinline LED also. I tried to wire this direct. It won't work, it flashes when you turn the turn signal on. A friend of mine recommended this after doing a search on the etrailer website. Etrailer support recommendation was installing two lights. Duh! that's why I wanted a third brake light, I already have two lights that function as stop/tail/turn. The installation in these pictures is not complete. I was trying to avoid drilling holes in the back of my trailer, I still may have to. I am going to enclose the wires going up the trailer to the light in some white wire loom. The light at present is secured with only white RTV, not sure that will hold. I'm still trying to avoid drilling new holes, may have to though. I hooked up all the wires on the input side, white to ground, green to right stop/turn, yellow to left stop/turn. I hooked only the red wire to red wire of the light on the output side. I hooked the ground (white wire) of light to input side of converter. Yes, it works and no it does not blink when either blinker is turned on. The additional two wires on the output side of converter are not being used nor is the additional wire of the light. Sorry for the long review, don't usually write reviews at all. Anyway, if this will help even one person it will be worth it.
I use Optronics oval LED lighting exclusively and I don't think this was made to work with them because of the rapid response of the LEDs. I use this so that on a 4 wire system I can have turn signals on the side of the trailer. When you first hit the brakes, there is a fast blip of light from the side marker/turn signals. With an incandescent bulb it would be too fast to light the bulb. This is something I can live with. I think this works great with no problems so far.
Used to add little LED marker turn lights on the corners to vintage two circuit airstream trailer. The led corner lights now are red running at night, red stopping by day and switch to yellow, when turning, day or night.
First off the customer service at etrailer is by far the best that I have dealt with. If I had a question, they sent me an email response very quickly. Secondly, the shipping is extremely fast. I placed the order and it came to an APO AE address (military stationed in Germany) via USPS Priority Mail and it arrived in like 5-7 days, I was shocked when it arrived, because I was expecting at least another 3 or 4 days. So, as far as the product. Works great and was just what was needed. Project was to make an adapter that I could plug into my 2017 Jeep Grand Cherokee U.S. spec and use a German trailer. My friend did all of the wiring and made the adapter, so I do not take any credit for any of it. Just sharing this, to those trying to figure out if it can be done. Moving on, the adapter is a 7 pin/blade normal American plug that goes into the back of the JGC and the other end of the adapter is the 13 pin German (European) socket. We tried it without this product and all worked except when you hit the brakes the brake lights were faded and the blinker lights were lit up as if they were the brake lights. So, had to get this product and separate the brake/blinker light on the American side and have separate brake and turn wires on the German side. Put this product between the two in the middle of the adapter, wired it up and all works great! I used 2 zip ties around the product and a bunch of electrical tape to hold it to the adapter, at least to give it a better look. Now I only have to plug in the adapter whenever I use a German trailer and all works correct. When done towing, remove the adapter and everything is back to the American system. Did not have to cut/splice or do anything to the wires on the JGC or the trailer, all was done at the adapter. Thanks again to etrailer for providing awesome customer support and shipping! Jeff
Interested in adding a third light up higher on your trailer for additional visibility? This product will separate the turn signal and brake signal on a four pin connector so you can add a running and brake light up higher to be visible. Simulates the third light that most cars and trucks have these days in the center of the back window. Positive for the semi-trucks visibility. You do not really think they can see the normal trailer lights 12" off the ground when following close behind or coming over a hill do you? Included a picture with just the running lights illuminated. Thank you etrailer for having the right products in stock! Most other dealers did not know what I was talking about and one even told me it was against the law. Called state highway patrol and they encouraged the additional third light! I also added the higher side running lights when semi's are merging behind you at night.
Easy install process, reviewed and illustrated in easy to follow wiring diagrams provided in the kit. etrailer on YouTube for the install of this tail light converter was complete and professionally illiustrated
Worked just like we needed it to. We used it for LED lights on a trailer we built and so had to add a tiny DC to DC voltage regulator to each light circuit. Use one with 12 Vdc output with as low as 5 Vdc input. Works good!
I was looking for a way to add a third tail light to a vintage trailer and this proved to be just the ticket. Easy to install and worked great right out of the box. Plenty of communications from etrailer staff along the way. Just wish they would provide tracking info so you could plan for expected receipt date.
This unit made it possible to split up the single wire for the brake and signal. Then made them 2 separate signals so i could hook up a 3 light trailer very nice
This converter is exactly what I needed to upgrade my 99 F350 tail lights to LED! The instructions are clear and straight forward. And I didn't need to modify any other part of the truck's wiring. (LED's themselves require a load resister wired in parallel to reduce the electrical current for slowing the flash rate.) Aside from that, this successfully separated the turn signal and brake wires.
Great service on a part I wasn't aware was available. Was going to use a 7 pin adapter to power seperate lights on a little camp trailer. This will simplify my needs. Thanks..
Shipping was fast. Installation was easy. Works as designed. Couldnt ask for a better result. Now my tow car is all wired correctly.
This product works as advertised, no complaints! I did have to do a little research on the different plugs as I was going from an American spec vehicle with the flat pin connector, to a European bike rack. Once I realized I needed to add a second ground wire from the vehicle to the rack, I was able to get it to work.
Easy painless installation! I used this product to install a third brake light on my TC Teardrop camper.
This product was used to separate the brake light signal from the turn light signal on a Ford F-350 cab/chassis with a flatbed to facilitate using amber turn signals without them illuminating when the brakes are applied (truck only, no trailer). So far they are "functioning as designed" and I'm very happy with the product.
Gregory V - 10/09/2019My taillight adapter arrived quickly, undamaged, and exactly as advertised. Prior to ordering, I emailed etrailer.com techs with a question. They responded quickly and with excellent advice. This little converter is simple to install. My trailer has a shared turn signal/brake wire. The adapter allows me to connect a lighted license plate frame that also has a third brake.
John D - 03/05/2015I used this to change the wiring and harness on a European trailer to work with my standard US 4-pin trailer outlet. Pretty simple and straight forward with the diagrams and write-ups that I found on this site.
Aaron - 03/27/2019We got three etrailer boxes via ups today. The box with the tow bar was damaged slightly so I opened and it seems fine. A bit more reinforcement is called for to prevent shipping damage concerns. Overall purchase experience was very good. I got good answers and guidance and felt valued. I’m planning to do the install myself and I feel comfortable doing so because of all their resources.
Added 3rd brake light to my 5th wheel. Simple connections and works great.
This is a very useful device for those of us who flat tow auxiliary vehicles, such as a tracker behind a motorhome or whatever. Also it is easy to install. Keith
Keith K - 07/15/2018Do you have a question about this Wiring?
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