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  1. Flat Tow Wiring Harness
  2. Roadmaster
  3. Diode Kit
  4. Splices into Vehicle Wiring
  5. Tail Light Mount
  6. Universal
Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 4-Way Flat Connectors
Roadmaster

Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 4-Way Flat Connectors

Part Number: RM-154
In Stock
$89.89
Flat Tow Wiring Harness

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This wiring kit carries your RV's brake and turn signals to your towed car's tail lights. Diodes prevent damage from electrical feedback. Connects RV and towed car with 4-pole flat plugs. Includes installation hardware. 1-800-940-8924 to order Roadmaster flat tow wiring harness part number RM-154 or order online at etrailer.com. Free expert support on all Roadmaster products. Great prices and Fastest Shipping for Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 4-Way Flat Connectors. Flat Tow Wiring Harness reviews from real customers.
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  • Reviews (800)
  • Q & A (0)
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Roadmaster Flat Tow Wiring Harness - RM-154

  • Diode Kit
  • Splices into Vehicle Wiring
  • Tail Light Mount
  • Universal
  • Roadmaster

This wiring kit carries your RV's brake and turn signals to your towed car's tail lights. Diodes prevent damage from electrical feedback. Connects RV and towed car with 4-pole flat plugs. Includes installation hardware.


Features:

  • Carries your RV's tail, brake, and turn signals to your towed car
  • Prevents feedback that can damage your vehicle's electrical components with diodes
  • Includes:
    • 4 Hy-Power diodes
    • (2) 4-Wire harnesses with 4-pole flat connectors
    • Butt connectors, 1 ring terminal, zip ties, and plastic loom


Specs:

  • Max amperage: 85 amps
  • Max voltage: 24 volts
  • Power cord: 6' long
  • 4-Wire harness: 30' long
  • Plastic loom: 3' long


Notes:

  • A brake light relay (RM-88400 - sold separately) may be required if used with a flat tow brake system. (See below.)
  • A wiring converter (118158 - sold separately) and 2 additional diodes will be needed to retain separate turn and brake signals. (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."


    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.


    To keep the separate lighting system on your car functioning properly while you're flat towing, add a wiring converter (118158 - sold separately) and 2 additional diodes.


    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.



    Wiring Diagrams for Roadmaster Diode Kit

    Diode Wiring Diagram

    Diode Wiring Diagram

    Diode Wiring Diagram

    Diode Wiring Diagram


    154 Road Master Universal Wiring Kit with 4 Hy-Power Diodes and 4 Wire Flat Trailer Connectors

    Compare to Tow Ready TR118821

    Installation Details RM-154 Installation instructions

    This Product Fits The Following Vehicles




    Customer Satisfaction Score:


    Customer Reviews

    Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 4-Way Flat Connectors - RM-154

    Average Customer Rating:  4.8 out of 5 stars   (800 Customer Reviews)

    This wiring kit carries your RV's brake and turn signals to your towed car's tail lights. Diodes prevent damage from electrical feedback. Connects RV and towed car with 4-pole flat plugs. Includes installation hardware.

    by:
    Jeep

    Straightforward install on my Jeep Gladiator and no issues.

    Steven

    8/21/2024

    Still works great after a year!



    by:
    2019 Jeep Cherokee

    Delivery arrived on time as promised well packaged for the trip across the nation. Everything is brand new and appears to be well made. I'll be installing next week and will let you know how it goes. With all the videos available, I think it'll be doable in my garage.



    by:

    Easy to install and video are great. Product is fine



    by:

    It does what it says on the tin. Easily lit up my XJ so I could tow it. Only regret is that by making the connections at the rear, you don’t get the front market lights on the toad. I should have connected the running lights diode in the harness under the dash so all the marker lights come on at night.



    by:

    Simple to install kit that does exactly as listed. Very thorough instruction that were easy to follow.



    by:
    2023 Ford Expedition

    Running the wires down the frame is hardest part. Instructions and video were spot on. Thanks



    by:

    Instructions were clear and easy to fol low.



    by:

    I’m always extremely satisfied with Roadmaster products. I had just bought a new truck and planned on towing it so I needed everything to get it ready to tow. This review also applies to to the other items I purchased.



    by:

    I thought I order the 7 to 6 pin wiring harness for my vehicle as I have the 7/6 cord I used when I pulled my pickup. I also ordered the 6 pin mounting bracket with the 6 pin adapter that wires into the harness. I received the kit which is a flat 4 pin harness.



    by:

    First of all Justin B,was awesome so very helpful and knowledgeable went over everything with me and then double checked what was needed before I placed the order for my 2022 maverick to be flat towed, order only took 3days to get to Fl.Kudos to Justin B all the guys putting together the order
    and etrailer awesome job,will definitely use them again for any of my needs.



    by:
    2015 Subaru Forester

    etrailer is a great company for towing products. They have fast delivery and they have nice installation videos. This order I added 2 more diodes to wire my 2015 Subaru Forester to have separate wiring for break, running, and turn signal lights.



    by:

    This system worked perfectly from experience. They help from trailers e trailer agents was crucial for guiding me through the process.



    by:

    Works perfectly and straightforward instructions made it easy to install.



    by:

    Installing it in my garage wasn't fun or easy but that's because jeep seems to change the wire colors year to year. Got it working after some trial and error



    by:
    2014 Chevrolet Equinox

    It is exactly as advertised, not yet installed but looks pretty self explanatory



    by:

    THE EQUIPMENT IS FINE. THE INSTALLATION VIDEOS ARE SUPERB. MAKING PURCHASING THIS PRODUCT VERY WORTHWHILE.



    by:

    I had this system professionally installed and have used it several times since. I am very happy with the performance.



    by:

    Installation instructions were great, no issues or questions. I ran the wire thru the frame, and used split wire loom and tape to protect wiring when outside the tube frame.



    by:

    Good instructions and easy to install.



    by:

    So far so good. Everything is working. ..



    by:

    the service was great, they went out of their way to make sure they were providing me with the correct part



    by:

    I have order several things from etrailer. Their products are great. Due to nobody's fault but my own I ordered some wrong things. The return was so easy, no questions asked. I would recommend this company to anybody.



    by:

    Installed in less than 30 min



    by:
    2019 Chevrolet Blazer

    Product is very well built and is hidden within the bumper/grille. Installation wasn't too difficult, reinstallation of front bumper requires 2 people.
    Pleased with end results.



    by:

    Great service and fast delivery
    I wished
    you guys match prices


    25
    800
    Show More Reviews

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