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Roadmaster Smart Diode Kit for Variable Voltage LED Tail Lights - 7-Way to 6-Way Adapter Cord
Roadmaster

Roadmaster Smart Diode Kit for Variable Voltage LED Tail Lights - 7-Way to 6-Way Adapter Cord

Part Number: RM63MR
In Stock
$203.77
Flat Tow Wiring Harness

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Smart diodes are our favorite option for getting brake and turn signals on your towed car. They are really well-made and reliable, plus pretty easy to install. This complete kit includes everything you need for multiplex LED tail lights. 1-800-940-8924 to order Roadmaster flat tow wiring harness part number RM63MR or order online at etrailer.com. Free expert support on all Roadmaster products. Great prices and Fastest Shipping for Roadmaster Smart Diode Kit for Variable Voltage LED Tail Lights - 7-Way to 6-Way Adapter Cord. Flat Tow Wiring Harness reviews from real customers.
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Roadmaster Flat Tow Wiring Harness - RM63MR

Features:

  • Smart diodes correctly display RV's brake and turn signals on your towed car with variable voltage LED tail lights
    • Converts the 12V signal from your RV to a 9V signal so your tail lights work as intended
    • Prevents feedback that can damage your vehicle's electrical components
    • Keeps the battery from draining while flat towing
    • Resists corrosion with powder coated aluminum casing
  • 7-Way to 6-way coiled adapter cable runs power from your motorhome to your towed vehicle
    • Coiled to prevent dragging and tangling
    • Resistant to wear and tear with durable vinyl casing
  • 6-Way socket hardwires to towed car and mounts with included bracket
  • Kit includes:
    • 2 Smart diodes
    • 4-Wire harness
    • 7-Way to 6-way coiled adapter cord
    • 6-Way socket with mounting bracket
    • Butt connector, split loom, ring terminals, zip ties, and installation hardware
  • Assembled in the USA


Specs:

  • Application: variable voltage tail lights with LED bulbs only
  • Maximum amperage: 5 amps
  • Maximum voltage: 16 volts
  • Wiring harness length: 27'
  • 14-Gauge wire length: 10'
    • Maximum power rating: 60 volts
    • Operating temperature: 40 F to 176 F
  • Coiled cable:
    • Max length: 8'
    • Compressed length: 15"
  • Limited lifetime warranty


Notes:

  • A brake light relay (RM-88400 - sold separately) may be required if used with a flat tow brake system. (See below.)
  • If your motorhome has a separate lighting system, where the brake and turn signals run on separate wires, you'll need a tail light wiring converter (RM-732 - sold separately) to complete this installation. (See below.)

review for diode kit

"Don't be intimidated by diodes: if you can strip and crimp wire, this installation will be no problem."


What are Variable Voltage Tail Lights?

A variable voltage tail light (also known as multiplex) uses the same wire for both the brake light and the tail light, sending a 12-volt signal to the brake light and a 9-volt signal to the tail light. This works fine when you're driving, but when you are flat towing, the RV will send a 12-volt signal to both the brake light and tail light, making them the same level of brightness and impossible to distinguish from each other. The drivers behind you won't be able to tell the difference between your tail lights and your brake lights, which is a huge safety issue.


These smart diodes solve that problem by simply converting the signal from the RV to the lower voltage needed for your car's tail lights. They install permanently, but don't worry; everything will work as normal when you're not flat towing.


What if I Have Incandescent Tail Lights?

This kit is designed to work with LED lights only, so if you have incandescent variable voltage lights, you'll need kit RM26FR (sold separately) instead.


Do I Need a Brake Light Relay?

If the engine is off and your car's brake lights illuminate when you press the brake pedal, you need to install a brake light relay (RM-88400 - sold separately) with this kit. Without a relay, your car's brake signal will override the turn signal sent by the RV when you are slowing down to make a turn, creating a potentially dangerous situation. Other drivers will see that you're slowing down, but not that you're making a turn. With a brake light relay, you can signal both and travel safely.


Combined Lighting System vs Separate Lighting System

Combined vs Seperate Lighting System

A combined lighting system, or 2-wire system, uses the same light bulb to signal both braking and turning. (In other words, the car signals a turn by flashing the brake light.)


A separate lighting system, or 3-wire system, has the brake signal and the turn signal light up independently of each other. Typically, the turn signal is amber.


If your motorhome has a separate lighting system, add a tail light wiring converter (RM-732 - sold separately) to keep your setup functioning properly.



Wiring Diagram for Roadmaster Smart Diode Kit

Smart Diode Wiring Diagram


152789 Road Master Wiring Kit with Smart Diodes for Variable Voltage LED Taillights

02427 14 Gauge Brown Primary Wire

146-7 Roadmaster 7-Wire to 6-Wire Flexo-Coil Kit

Installation Details RM63MR Installation instructions

This Product Fits The Following Vehicles



California residents: click here


Customer Satisfaction Score:

Ratings & Reviews

4.7

318 reviews
Smart diodes are our favorite option for getting brake and turn signals on your towed car. They are really well-made and reliable, plus pretty easy to install. This complete kit includes everything you need for multiplex LED tail lights.

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See what our Experts say about this Roadmaster Flat Tow Wiring Harness

  • Will Hopkins Flat Tow Wiring Work with LED Lights and Sensors on a 2024 Jeep Wrangler JLU
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  • Flat Towing Components Needed For A 2022 Jeep Cherokee Trailhawk
    Hey Tim, Those are both great choices for getting your Cherokee flat tow-ready, however you'll also need a few more components to complete your setup. If you go with the Blue Ox Avail Tow Bar # BX7420 then you'll want to go with the Blue Ox Baseplate # BX1143 to avoid having to purchase any additional adapters. The Demco Stay-IN-Play Duo # SM99251 is one of my most recommended braking systems but is designed for hydrualic braking systems. If your motorhome has air brakes you would want...
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  • Blue Ox Flat Tow Setup for 2022 Jeep Cherokee Trailhawk
    Hey Carl, welcome back! For a Blue Ox setup to flat tow your 2022 Jeep Cherokee Trailhawk I recommend the following: -Blue Ox Base Plate Kit - Removable Arms # BX1143 -Blue Ox Alpha 2 Non-Binding Tow Bar # BX7380 (includes safety cables) -Roadmaster Smart Diode Kit for Variable Voltage LED Tail Lights - 7-Way to 6-Way Adapter Cord # RM63MR -Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 -Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes # SM99251 OR -Demco...
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  • Recommended Flat Tow Wiring for a 2024 Jeep Gladiator with LED Tail Lights
    Thanks for reaching out, Todd! The flat tow wiring kit I recommend for the LED tail lights on your 2024 Jeep Gladiator is the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit, and the correct part depends on if your Gladiator has the ParkSense feature or not: - With ParkSense # RM63MR - Without ParkSense # RM-15267 I think since you have the LEDs that you're supposed to have the ParkSense, but it's best to double check since the ParkSense kit has different diodes to help the...
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    I sure can Galen, and thanks for the information. Since your Tiffin motorhome has the air line connection you'll need the Demco Air Force One Flat Tow Brake System for 2020 and Newer Tiffin Chassis RVs w/Factory Air Brakes item # DM55MV. This comes with all the components necessary for install on your Jeep. The included air line will connect directly to your Tiffin. Here are the rest of the parts you will need to flat tow your 2025 Jeep Wrangler Sport: Tow Bar and Safety Chains - etrailer...
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  • Will Roadmaster Falcon Tow 2025 Jeep Grand Cherokee Overland
    Hi John; as long as you aren't exceeding that 6,000 lb capacity it won't be a problem so you can use the Falcon to tow your 2025 Jeep Grand Cherokee Overland. Since the Overland has tow hooks the correct Roadmaster Direct-Connect Base Plate Kit is the # RM77ZR. Since you want to use the Blue Ox Patriot # BLU37TR you will also need the 12 Volt Outlet Kit, 20 amps # RM-9332. If you need new wiring the Roadmaster Smart Diode Kit for Variable Voltage LED Tail Lights # RM63MR is the best option...
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  • Flat Tow Set Up For a 2026 Jeep Wrangler
    Hey, Skip! Happy to help get your new Jeep set up for flat towing. There is going to be a list of parts, so I'll go ahead and list them all below for ya. Blue Ox Base Plate: Part # BX1139 Blue Ox Avail Non-Binding Tow Bar: Part # BX7420 Demco Stay-IN-Play Duo Braking System: Part # DM86VR Roadmaster Stop Light Switch Kit: Part # RM-751490 Roadmaster Battery Charge Line Kit for Towed Vehicles: Part # RM-156-25 (to keep your battery charged while flat towing) Roadmaster 4-Diode Universal...
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    hey, Chuck! Happy to help out here! Since you already have a Blue Ox tow bar I'd stick with getting another Blue Ox base plate, part # BLU53FR. This works if you have a factory plastic bumper, Mojave, Rubicon with factory plastic or steel bumper. If your Gladiator is equipped with D-rings that are flat tow rated you can use part # BX88358 for 1" D-rings or part # BX88357 for 7/8" D-rings. It sounds like you also want all the other parts so I'll list the rest of the parts below for ya....
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  • Recommended Flat Towing Parts for a 2022 Jeep Wrangler 4xe w/a Factory Winch Bumper
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  • Recommended Flat Towing Parts for a 2023 Jeep Wrangler 4xe
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  • Flat Towing Components Needed For A 2024 Jeep Gladiator
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  • Can A Baseplate Be Installed In A 2023 Jeep Grand Cherokee Summit With Active Air Shutters
    The compatible baseplates for a 2023 Jeep Grand Cherokee do not have any tech listings against usage with active air shutters so there shouldn't be any interference. That being said most of the time if there is any interference you can simply trim the air shutters causing the interference and finish installing the baseplate. Before installing anything you should also verify your specific model is capable of being flat towed by looking up the recreational towing or dinghy towing section...
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  • Blue Ox Base Plate and Tow Bar Wiring for 2025 Jeep Wrangler Rubicon
    Hey Stephen! The 2025 Jeep Wrangler Rubicon has the factory steel bumper so you need the Blue Ox Base Plate Kit # BX1139. If you do not have ParkSense you can use the Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles # RM-15267. If you do have ParkSense you need the # RM63MR instead. Then to add a charge line you can use the # RM-156-25. If you don't have a 12V outlet to power your Patriot you can add one using the # RVI37FR. Any big trips planned once you get your Wrangler...
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  • Recommended Parts for Flat Towing a 2021 Jeep Cherokee
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  • Parts Needed to Flat Tow 2021 Jeep Gladiator
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  • Does 2019 Jeep Wrangler Unlimited With ParkSense Require Smart Diode Kit
    Hello Mike; I'm sure this happened because we don't have any notes on ParkSense for the 2019 models. The same is true for Roadmaster. It looks like ParkSense started in 2018 but the smart diode kit # RM63MR isn't listed for models before 2021. I asked Roadmaster about this and they weren't 100% sure what the reasoning was but I can help you find out which kit is correct. Take a look at the pictures below from the Roadmaster TSB. If you have those tail lights marked yes then you have proximity...
    view full answer...


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