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Vehicle to Vehicle Tail Light Converter

Vehicle to Vehicle Tail Light Converter

Item # 118158
Retail:$58.78
Our Price: $36.04
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Shipping Weight: 0.49 lbs
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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. 1-800-940-8924 to order Tow Ready accessories and parts part number 118158 or order online at etrailer.com. Free expert support on all Tow Ready products. Great prices and Fastest Shipping for Vehicle to Vehicle Tail Light Converter. Accessories and Parts reviews from real customers.
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Tow Ready Accessories and Parts - 118158

  • Trailer Wiring
  • Mounting Hardware
  • Brackets
  • 7 Round
  • 7 Round
  • Tow Ready

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:

  • Used when a motorhome is towing another vehicle by way of a tow bar
    • If the towing vehicle has a 2-wire system and the vehicle being towed is on a 3-wire system (the vehicle has amber turn signals, separate from the brake signals), the vehicle to vehicle tail light converter will need to be used
  • This item cannot be installed backwards (the input going to the output side) to convert a tow vehicle down
  • Will not work with vehicles that have LED tail lights
  • Limited 1-year warranty


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.



118158 Vehicle to Vehicle Taillight Converter

Replaces 31820

Installation Details 118158 Installation instructions


California residents: click here


Customer Satisfaction Score:


Customer Reviews

Vehicle to Vehicle Tail Light Converter - 118158

Average Customer Rating:  4.8 out of 5 stars   (153 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.

by:

The tail light converter worked better than expected. Successfully added a third brake light to a unique trailer. Took the guesswork out of project with the instructions provide.



by:

Product does its job, the 5 star review is because of etrailer. They provide lots of get information upfront and have wonderful tech support. They have earned my business.



by:

This 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.

Peter

10/11/2021

No problems so far



by:

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.

Sam

5/6/2015

Does the 3rd brake light flash when using the hazard lights?

Anonymous

5/24/2015

Yes, emergency flashers will flash the third light also.



by:

I wanted to covert a rear, high, center, red light from a running light to a 3rd brake light. This was the answer. It took less than 1/2 hour to plan and install this converter and it works perfectly. I now have a 3rd brake light on my Off Grid Trailers Pando 2.0.



by:

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.



by:

This 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.



by:

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



by:

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.



by:

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.



by:

Installed correct. However, can tell the lights are now dimmer than before installing the converter. Not to happy with dim brake lights.
The converter works as said otherwise.

Etrailer Expert

Jenny N.

5/19/2023

I wanted to ask you if your vehicle has LED lights? I know that this converter will work correctly if the trailer has LED lights, however will not if the tow vehicle has them.



by:

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.



by:

The VtoV converter works great and solved a problem I have been dealing wiht for almost 6 months.
My one suggestion to anyone adding a trailer harness to a vehicle that was also wired for flat towing by an rv, that you realize and understand the difference between two wire and three wire systems. This description can be found in ETrailers videos. I found after much frustration I needed this unit because the two wire system coming from my RV conflicted with the plug and play trailer harness. It separated the incoming signal into a 3 wire system allowing my Jeep to operate as designed, and the trailer harness to also work.
As good and helpful everyone at ET have been I only wish we could have identified the conflict sooner.
But overall, I will recommend and use ETrailer again.



by:

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..



by:

Since my trailer is 100% LEDs, I would not have chosen this for the two to three wire conversion since the description specifically states "not for LEDs". But after a discussion with the tech guys, I installed it and it has worked flawlessly.

K.j.

2/2/2023

Still working perfectly!



by:

It work great 1st try



by:

Easy painless installation!
I used
this product to install a third brake light on my TC Teardrop camper.



by:

Great company very helpful



by:

Shipping was fast. Installation was easy. Works as designed. Couldnt ask for a better result. Now my tow car is all wired correctly.



by:

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.

4/6/2021

The tail light converter is still working fine. I have no regrets.



by:

My 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.

3/5/2015

What great customer service! You guys and your products are fantastic. The items I bought are working 100



by:

The perfect solution to hook european trailers with separate blinker and brake lights to U.S. vehicles that combine the two. Piece of cake to install, works great. Many props to E-Trailer for supporting the troops by providing shipment to APO/FPO. Note, The trailer ground passes over this devise to the ground coming from your vehicle. Not clarified in the instructions but easy enough to figure out.

Martin S.

1/16/2015

Still loving it.Thanks, Marty



by:

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.

3/1/2021

Still working flawlessly, even with lots of snow, ice and sludge



by:

I 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

3/27/2019

The parts are still on my European trailer and working well! The trailer is a German brand and started its life there in Germany being pulled by my American-spec Jeep Wrangler. The trailer’s wiring and the Jeep’s connections needed to be massaged in order to work. The parts I ordered from etrailer and the writeups for the project on your site made it all possible. Now the trailer is titled and registered in Virginia and enjoying its life on this side of the Pacific!



by:

I received the trailer wiring adapter in just a couple days. It contained very easy instructions and the wiring leads were a very generous length.
It only took me a few minutes to install and it works perfectly.

Thank you !

Tyler

5/25/2019

Fantastic !! Works perfectly, no problems whatsoever


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153
Show More Reviews

See what our Experts say about this Tow Ready Accessories and Parts

  • How to Get Separate Turn Signals and Brake Lights to Work on a Trailer
    If your trailer has separate turn signals from the brake lights and you want them to remain that way, you will need to use a special converter. On the trailer side, behind the 7-Way, you will attach the Vehicle to Vehicle Taillight Converter, # 118158. On the 7-Way wiring, locate the wire for the left turn and brake and attach it to the yellow wire on the converter input side. Connect the wire from right turn and stop to the green wire input side. Ground the white wire to the trailer frame. On...
    view full answer...
  • Converter to Separate Turn Signals and Brake Lights on 2011 Ram 2500
    You are correct that you can use Vehicle to Vehicle Tail Light Converter # 118158 to separate the brake and turn signals on your 2011 Ram 2500. The only thing to note is that this converter does not work with LED lights.
    view full answer...
  • Signal Converter Recommendation for Wiring in Third Brake Light for Trailer
    For separating out a dedicated brake light signal for powering a trailer's third brake light the converter box part # 118158 would be exactly what you need. Once wired in the red wire of the converter is what you'd run to the third brake light.
    view full answer...
  • Trailer Left Turn Signal/Brake Signal Circuit Has No Power on a 2001 GMC Yukon Connector
    You probably just have a blown tow package fuse on your 2001 GMC Yukon. Under the hood in the power distribution box there is a fuse labeled TRL L TRN. This is the fuse for the trailer left turn signal circuit. There are also fuses for the Stop lamp and CHMSL circuits that you can check.
    view full answer...
  • Why Does Converter 118158 Need Left and Right Blinker/Stoplight Circuits to Function
    The reason part # 118158 needs both left and right turn signals to identify the convert the signal to stop light only circuit is that the converter knows that when both circuits are activated the stop lights are on and then it gives the stop light wire voltage. With only one side of wiring activated it wouldn't be able to differentiate between the blinker circuit and the stop light since both put 12 volts on the circuit.
    view full answer...
  • Does the Vehicle to Vehicle Tail Light Converter Work with LED Lights
    Vehicle to vehicle converter # 118158 works if the TOW vehicle has regular lights and the dinghy (vehicle being towed) has LED lights. So basically the input source has to be 12 volt incandescent lights. I have linked a demo video for you.
    view full answer...
  • What Lighting System is on a 2003 Cadillac Escalade
    The tail lights on your 2003 Cadillac Escalade use a seperate lighting system which means the turn signal and brake lights are on different circuits. The runnings lights will be carried on the brake light circuit. I am not sure what you mean or the issue you are having but the turn signal bulb, not to be confused with the brake/running light bulb should only illuminate while the turn signal is active. If it this is not the case then you have an issue and will need to take the vehicle into...
    view full answer...
  • Where Do Extra Diodes Go When Wiring A Tow And Towed Vehicle With Separate Brake And Turn Signals
    The other two diodes are needed so you can have separate turn and brake signals. So you will have a diode for each brake light (right and left), a diode for each turn signal (right and left) and a diode for each tail light (right and left). I will send you a link to the wiring diagram of the # RM-154 wiring kit to show where all of the diodes are connected and what color wires go to what function on the tow vehicle. A separate wire for the brake circuit will have to be run on the towed...
    view full answer...
  • Can Converter # 118158 be Used to Give a Truck with Combined Circuits a Dedicated Turn Signal
    To give your truck an additional set of dedicated turn signals the part # 118158 would be what you would need. On the input side of the box you would need to tap the yellow and green wires into the combined circuit taillight circuit of the vehicle and then use just the yellow and green wires on the output side for the turn signals. Yellow goes to the left, driver side and the green goes to the right, passenger side.
    view full answer...
  • Installing Side Trailer Lights to Blink with Corresponding Turn Signal
    If you are wanting to install side marker lights on your motorcycle trailer that blink with the turn signal, it will need to be tapped into the turn signal/brake light wire for that side. However, just doing this will also allow the side light to come on with the brake lights. You do not want to attach it to the running light circuit, as this would back feed and force the lights to come on when they should not. Trailer have combined turn signals and brake lights and the running light...
    view full answer...
    Image 1 for
  • How to Wire 3-Function Reverse/Turn/Stop Light in Vehicle with Combined Stop/Turn Wiring
    In order to install your 3-function lights on your 1997 Dodge Ram 3500 that has combined stop/turn wiring you will need a vehicle-to-vehicle taillight converter, part # 118158 from Tow Ready. This converter separates the combined stop/turn functions into separate signals that run on separate wires. This converter will work only on incandescent lights, but not with LEDs. Your vehicle running/tail light wire will bypass the converter and go directly to the wire on your lights that operates...
    view full answer...
  • Converting a US 4-Way to European 7-Way
    In order to get the US style 4-Way to work with the European style 7-Way you are going to have to do a little hardwiring. What you will need is a vehicle side European 7-Way and a special converter, # 118158. You will have to cut off the 4-Way on the vehicle. The wires left over should be white for ground, brown for running lights, yellow for left turn/brake lights, and green for right turn/brake lights. On the input side of the converter match up the wires color for color. Brown will...
    view full answer...
    Image 1 for
  • Can a Taillight Converter Work with a 2005 Chevy Corvette C6
    The taillight converter # 118158 you referenced will separate the blinker from the brake light on your Chevy Corvette C6. You won't lose any amperage. However, converter # 118158 will not work with vehicles that have LED taillights. I am thinking your Corvette will have LED taillights. The converter is really designed to be used when a motorhome is towing another vehicle by way of a tow bar. I added a video review for you as well.
    view full answer...
  • Taillight Converter for European Trailer
    The Tow Ready Vehicle to Vehicle converter, part # 118158 will indeed split the brake light circuit back out from the right and left turn circuit, so it will indeed do what you're wanting it to do. We do not ship to Europe, so if you have a friend or relative in the US, you could have them order the item for you and then have it shipped to you in Europe. Another alternative would be to use a freight forwarding service, which you can find online.
    view full answer...
  • Troubleshooting Wiring on a Trailer with Separate Brake and Turn Signal Lights
    There are two things that may help to solve your predicament. The easier one is the converter. The converter that you used, part # 118158, is not compatible with LED lights. So, even if the wires all lined up where they needed to go, it wouldn't have worked anyway. We don't currently carry a 2-to-3 converter compatible with LEDs. As for the wiring, that's a little harder to figure out. From what I can tell, you might be using a wishbone 4-way harness on your trailer. These differ from...
    view full answer...
  • Vehicle to Vehicle # 18158 Taillight Converter for Separate Turn Signals on 2003 Jeep Wrangler
    For what you are trying to accomplish, you shouldn't need the diodes. The # 118158 vehicle to vehicle taillight converter you referenced would convert the 3 wire system you have now to the 4 wire system you want. Diodes are for use when one vehicle is towing another, and you don't want the signal from the towed vehicle feeding back into the electrical system of the tow vehicle. I'd recommend installing the converter in an interior location if at all possible. The converter isn't designed...
    view full answer...
  • How to Add Dedicated Turn Signals to a Trailer with Combined Function Taillights
    I know what you are trying to do, and it is possible with the part # 118158. To add a separate turn signal on your trailer you would use the # 118158 to just tap into the trailer turn signal/brake light circuits but you would not interrupt the circuit that runs back to the taillight assemblies. This way the output side of the converter box will have the separate taillight signal for you to run to the additional turn signal and the rear taillights will still be combined. I attached a diagram...
    view full answer...
    Image 1 for
  • Troubleshooting No Trailer Brake Light When Connected To 2002 Jeep Grand Cherokee
    Your 2002 Jeep Grand Cherokee has separate turn and stop lights. Your trailer however has left turn and stop combined as well as right turn and stop combined. So, you need a converter like the Vehicle to Vehicle Tail Light Converter # 118158. This converter will take the separate signals and combine them to work properly with the dual filament bulbs on your trailer. A converter like this is already integrated into the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer...
    view full answer...
  • Are Turn Signals on When Brakes are Applied With Converter 118158
    When you hit the brakes and use the turn signals on your vehicle, the brake lights will be on with the turn signals when using the Vehicle to Vehicle Tail Light Converter # 118158.
    view full answer...
  • Converter to Separate Out Stoplight Circuit from Stoplight on Truck Wiring
    To separate out the turn signals from the stoplight circuit you'd need a converter like part # 118158 and you'd be set.
    view full answer...
  • Converter Recommendation for 1987 Jeey YJ for Adding Third Brake Light
    What you need is a signal converter like the part # 118158 that you referenced. This will wire to your vehicle wiring that has the turn signals and stop light circuit on the same wire so that you can separate them out to get a dedicated stop light circuit.
    view full answer...
  • Are Diodes Required to Separate Brake Lights from Turn Signals Using Converter 118158 on Trailer
    That is exactly what converter # 118158 was designed for. You will not have to use diodes, although you could if you wanted and it wouldn't hurt anything, because there is only one input circuit for each of the wires. The red output wire would go to the brake light wire on each tail light. Yellow would go to left turn signal and green would go to right turn signal.
    view full answer...
    Image 1 for
  • Trailer Wiring for 2007 Jeep Wrangler Towing Utility Trailer with LED Lights
    All of the 4-pole flat trailer wiring harnesses we offer for your 2007 Jeep Wrangler (shown on the link at right) do not have built-in converters; they pull the power for the trailer's lights directly from the Jeep's taillight wiring. On a 4-pole vehicle connector the stop and turn signals are already combined; the yellow wire carries left turn and stop signals and the green wire carries right turn and stop signals. The brown wire carries running light signals for both sides of the trailer. It...
    view full answer...
  • Brake Lights are Dim With Turn Signal Flashing Using Converter 118158 On a Trailer
    The LED light warning is in reference to flat towing a vehicle that has LED lights. So basically for your situation the trailer (vehicle) LED lights could be the issue. An easy way to determine if it works better with incandescent bulbs would be to replace an LED brake light with an incandescent light of some kind and see if the problem persists. If it does persist then the issue could be related to the fact that converter # 118158 is not rated very high. This is just the nature of this...
    view full answer...


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