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Diode kit allows you to use your vehicle's tail lights and wiring system while preventing feedback from your RV. Wires 2-wire and 3-wire systems to operate as a combined lighting systems. Connectors and Extension loop sold separately.
Features:
Specs:
Note: For applications that have separate lighting, this kit will cause your brake lights to function as both brake and turn signal lights. A wiring converter (118158 - sold separately) and 2 additional diodes will be needed if you want to retain separate turn and brake signals.
Separate vs. Combined Lighting Systems
Some automobiles operate on a 3-wire system, wherein the brake signal and the turn signals travel along different wires to illuminate different lights. (Typically, these vehicles have amber turn signals.) This is referred to as a "separate lighting system". When you hook up for flat towing using this kit, your towed car's lighting system will operate in a combined fashion regardless of whether it typically has combined or separate lighting. This means that the brake and turn signals sent by your RV to your towed car will be carried on a single wire. As a result, your car's brake lights will do the flashing for the turn signals. Your vehicle will still function as designed when not hooked up to your RV.
Do You Need a Brake Light Relay?
Because this kit wires your vehicle as a combined system, a brake light relay (RM-88400 - sold separately) may be required if you use a supplemental braking system with your towing setup. A supplemental braking system depresses the brake pedal in your towed car every time you apply the brakes in your RV. So, if your towed car's brake lights illuminate when the brake pedal is pressed and the engine is off - as is the case when towing - then you need to install a relay to ensure that the lights on your towed car always act in accordance with the signals sent by your RV via the wiring harness. Without a relay, the brake signal from your towed car will override the turn signal sent by your RV when you slow down to make turns, creating a potential hazard.
California residents: click here
easy to use - just don't be like me and think you can hook turn signals to turn signals and brake light to brake light... ACTUALLY read and understand the instructions before cutting into your car's wiring harness... now i have turn signals for brake lights :-D but it's done and now "certified good enough"
have successfully completed the installation of the following items that I purchased from etrailer:
> Nighthawk RM-676 tow bar
> RM-524458-5 base plate
> DEMCO Stay in play DM86VR
> RM-152 diode wiring kit
> RM-156-25 charge wire kit
> RM-88400 brake switch relay kit
I work slow but methodically. I had no issues other than the high degree of difficulty for a 68 y/o man working alone. This project exceeds the abilities of someone NOT mechanically inclined. There is also the need for some specialty tools. I found that feeding the wiring through the dash, firewall, and underbody was more difficult than installing the front baseplate. Overall, I am satisfied with the function of this installation. I am glad I did it myself rather than having it done.
Tow vehicle: 2021 Entegra Emblem 36U
Towed vehicle: 2018 Ford Fusion Platinum Energi
This kit is pretty straight forward. Installed and works well like the installation says it should.
Ronald
7/22/2025
It works as advertised, etrailer always represents well.
Just finished installing the “kit”, everything went well, the video on the etrailer web site helped but was slightly different than my installation since it was a 2006 model and mine is a 2012.
Should make towing and hooking/unhooking easier and safer than using the magnetic lights.
I’m using the Pollack 6 pin connector with the wiring “kit”.
Steve C.
3/4/2020
Works Great, Totally Transparent During Towing or Normal Use
Awesome. Every time I have a question or need assistance, Etrailer employees are outstanding and very, very efficient.
Fast shipping and good price.
Just FYI, I would like to see enough plastic wrap included to cover the entire wire from the 6 way plug to the tail lights.
I have a 2025 Grand Cherokee L Summit reserve. I tried to route the wiring to be the most protected. I was short about 6 feet of wire. I did not strip off the white wire and I routed all four wires to both sides even though I did not need to. By doing this I was able to use the correct color code for left or right.
Bought as part of the installation of the Invisi-brake system and installed as part of the lighting system. Does the job for which it is designed. All lights work as they should.
Good instructions and straightforward to install.
Installation was easy with the directions and the video.
This was easy to install. I have used it for a year and have had no problems. I would recommend this.
Works great, easy to hook up and away we wenr
E Trailer staff goes above and beyond with Customer Service and Quality Equipment!!
Product came on time. Installed per ins tructions
Great customer service.
Sarah was very pleasant and profesional your company is lucky to have her.
Installed easily and have had no issues with it.
Great product and easy to follow instructions and video for installation.
This review is for E-Trailer. I ordered a complete dinghy towing set-up for the dinghy as a towbar came with the RV we purchased. I called E-Trailer and spoke with a very knowledgeable young lady and when I told her what I needed in layman’s terms she came up with what I would need to complete the dinghy preparation in order to safely tow it behind our RV. Everything they said it would do went just as the instructions directed. I ordered a Roadmaster Falcon 2 set up for the dinghy and they suggested a Blue Ox self contained braking system for the SUV itself. hey also suggested the complete wiring system and plug for the dinghy. To my amazement after the RV and dinghy were connected that also was as easy as they said it would be. Our first tow with the dinghy was great and the unhooking was also a very easy experience. This company was awesome to work with. Thank you for your knowledge and great products.
Installed a Blue Ox Base Plate kit on a 2015 Cadillac SRX. The base plate arrived promptly and was well packaged considering its weight. Watched the videos etrailer provides and used them as a step by step video guide. The videos were a big help. Installation is not too difficult if you're mechanically inclined. Had someone help with the installation but one person can perform the installation. I think the base plate is well engineered and everything fit as it should. Love the fact the installation is so well hidden. We have about 400 miles on the installation and have had no issues. Thanks to etrailer for a great price, great service, and great product support.
Hey George, just dropping a short line to let you and etrailer know that I'm definitely satisfied with your products. I'm using both the diode wiring kit and front tow hitch to tow behind the motorhome. Both have worked well over the past year. Your online videos were also a great help in understanding how and why your products work. I look forward to reaching out to etrailer again if/when I need additional upgrades to my Jeep.
Negative battery disconnect system started not working after less than a year
Had to go to local Chevy Dealer to have the battery disconnect system disconnected as was causing whole electrical system to shut down at inadvertent times
Jenny N.
9/25/2023
The wiring kit does have a limited lifetime warranty and I wanted to ask if you have reached out to Roadmaster?
After one year, one of the components installed in my truck's rear tail light was fried making my tail lights not work (even when not being towed). I called etrailer and told them the situation. JT was very helpful in setting up an appointment and getting the part fixed (under warranty). Slight annoyance followed up with good customer service.
It fits the bill--when they say universal that's correct; may not be a "factory" wiring harness but our Super Beetle is 45 yrs old.
Excellent service, knowledgeable and patient. Quick delivery, All excellent!
William
9/10/2024
Perfectly
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Jeffrey
11/19/2022
I have no regrets with this purchase. Items preform as advertised with no issues. I am very satisfied with Roadmaster and Demco products.