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  1. Flat Tow Wiring Harness
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  3. Diode Kit
  4. Splices into Vehicle Wiring
  5. 4 Flat
  6. Universal Fit
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
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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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Roadmaster Flat Tow Wiring Harness - RM-154

  • Diode Kit
  • Splices into Vehicle Wiring
  • 4 Flat
  • Roadmaster
  • Universal Fit

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



    California residents: click here


    Customer Satisfaction Score:

    Ratings & Reviews

    4.8

    3144 reviews
    5 Stars
    (2687)
    4 Stars
    (301)
    3 Stars
    (68)
    2 Stars
    (30)
    1 Star
    (58)
    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.

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    Show More Reviews

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