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Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights

Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights

Item # RM38FR
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Tow Bar Wiring

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RM38FR - Universal Roadmaster Splices into Vehicle Wiring
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This complete kit includes everything you need to connect your RV's tail, brake, and turn signal lights to your vehicle with variable voltage lights while flat towing. 7-Wire to 6-wire cord and 6-way car-side socket included for easy hookup. Lowest Prices for the best tow bar wiring from Roadmaster. Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights part number RM38FR can be ordered online at etrailer.com or call 1-800-496-5010 for expert service.
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  • Reviews (10)
  • Q & A (0)
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  • Why etrailer?

Roadmaster Tow Bar Wiring - RM38FR

  • Diode Kit
  • Splices into Vehicle Wiring
  • Universal
  • Roadmaster

This complete kit includes everything you need to connect your RV's tail, brake, and turn signal lights to your vehicle with variable voltage lights while flat towing. 7-Wire to 6-wire cord and 6-way car-side socket included for easy hookup.


Features:

  • Complete wiring kit lets you connect your RV's tail, brake, and turn signal lights to your towed car's lighting system
  • Smart diodes ensure that your variable voltage, LED tail lights function as they should while your car's being towed
    • Converts the 12V signal from your RV's wiring to a 9V signal so your tail lights work as intended
    • Prevents electrical feedback that can damage your vehicle's electrical components
  • 7-Wire to 6-wire Flexo-Coil adapter cord lets you easily run power from your motorhome to your towed vehicle
    • Expands out to 8' to prevent dragging and tangling
    • Resistant to water, oil, and chemicals and has silicone-injected plugs to prevent corrosion
  • 6-Way socket wires to harness and mounts on towed car with included bracket
  • Powder coated aluminum casing on diodes is corrosion resistant and provides protection from the elements
  • Kit includes 2 smart diodes, wiring harness, split loom, ring terminals, zip ties, 7-wire to 6-wire adapter cord, 6-way socket with mounting bracket, and 10' of 14-gauge wire
  • Brake light relay (RM-88400 - sold separately) may be required if used with supplemental braking system
  • Assembled in the USA


Specs:

  • 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 cord max length: 8'
  • Coiled cord retracted length: 15"
  • Limited lifetime warranty


This complete smart diode wiring kit lets you connect your RV's tail, brake, and turn signal lights to your towed car's lighting system so that you'll have the signal lights necessary for flat towing your vehicle.


Because your vehicle has variable voltage tail lights, you cannot use a standard diode wiring kit to get these signal lights. If regular diodes are used on a vehicle that has variable voltage tail lights, the bulbs will light up as though the towed car is braking whenever the tail lights are on. In other words, there will be no difference between your vehicle's brake lights and running lights. This is because variable voltage tail lights use the same wire to power both the brake lights and tail lights. They do this by using a 12-volt signal for brake lights and a 9-volt signal for tail lights.


Smart diodes correctly modulate the 12-volt signal coming from your RV to activate only the intended circuit. The result is that your vehicle's tail lights will look and function as intended.


This wiring kit includes everything you need to hook up your motorhome's electrical to your towed car. It is designed to work with LED lights only. If your vehicle has incandescent lights, you'll need to use the smart diode kit designed for incandescent tail lights (RM26FR - sold separately) instead.


If your RV has separate tail light wiring, wherein the brake and turn signals run on separate wires, you'll need a wiring converter (RM-732 - sold separately) to complete this installation.


Smart Diode Wiring Diagram


153789 Roadmaster Wiring Kit w Smart Diodes for LED Bulbs

02427 14-Gauge Brown Primary Wire

146-7 Roadmaster Adapter 7 to 6 Wire Flexo-Coil Cord

Installation Details RM38FR Installation instructions

This Product Fits The Following Vehicles





Customer Reviews

Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights - RM38FR

Average Customer Rating:  4.7 out of 5 stars   (10 Customer Reviews)

This complete kit includes everything you need to connect your RV's tail, brake, and turn signal lights to your vehicle with variable voltage lights while flat towing. 7-Wire to 6-wire cord and 6-way car-side socket included for easy hookup.

- RM38FR
by:

I ordered an in stock item on Thursday but did not receive it until 9 days later. Maybe I didn't order it correctly to receive it sooner. I don't think a picture will show the products on my vehicle. That is a great thing!



- RM38FR
by:



- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring


Works like towing a trailer, The wiring was a challenge and the E-Trailer video on installatios was very helpful



- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring


This is to rig my third vehicle for flat towing behind our motorhome. I am sure that the e-trailer people will be available to help me if I need advice.



- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring


Work as advertised - no issues



- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring


Installation went very well with the help of the video on your website. Thanks.



- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring




- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring




- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring




- RM26FR
by:

Review from a similar Smart Diode in Tow Bar Wiring



10
10

Ask the Experts about this Roadmaster Tow Bar Wiring



  • 2021 Chevy Trailblazer LED diode wiring
    Using the Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights Item # RM38FR you'll want to cut the diodes in just before the the twist-lock to the LED and another just before the incandescent bulb. The point of the diode is to stop power from reversing and damaging the wire behind it so being closer to the bulbs will help save wire in the event that there is a power surge. Hooking up diodes to your car will not cause the LED or signal lamp to act any...
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    It looks like you've got a good handle on what you need to flat tow your TrailBlazer. You will indeed need a stop light switch, part # RM62FR. Also, per the owner's manual, you'll need to disconnect the negative battery terminal before towing. A quick disconnect, part # RM-766 is available. The kit includes a switch that mounts in the passenger cab of the vehicle that allows you to disconnect and connect the battery remotely without needing to go into the engine compartment and disconnect...
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  • Comparing Roadmaster and Blue Ox Base Plate Kits For 2021 Ford F-150 4WD
    If I was installing a base plate kit on my 2021 Ford F-150 4WD to flat tow it I personally would go with the Roadmaster Direct-Connect Base Plate Kit # RM38VR over the Blue Ox # BLU33FR. This is simply due to preferring the Roadmaster tow bars over the Blue ox options, though both brands are well known and very reliable so you really cannot go wrong with either option especially since both of these above base plate kits install in a very similar manner, and both have removeable arms so...
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  • Does Roadmaster Flat Towing RM-155 Bulb and Socket Kit Fit a 2020 Chevy Equinox
    It will depend on the trim level of your 2020 Equinox. If it's an L, LS or LT model, you will be able to use the # RM-155 Roadmaster bulb and socket kit. If it's a Premier model, you'll need to use a different option. The Premier model uses variable voltage taillights that would require a smart diode. If the taillights on the Premier model are incandescent, use # RM26FR. If they're LED, use # RM38FR. I've linked to some installation videos that you might find helpful.
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    To tow your 2021 Ford F-150 you'll need a tow bar, base plate, braking system, tow bar wiring kit, and safety cables. I have the following recommendations for you below: Tow Bar: Roadmaster BlackHawk 2 All Terrain, Non-Binding Tow Bar # RM-422. This tow bar features a non-binding design and large hookup radius to make hooking and unhooking your vehicle on any terrain a breeze. Base Plate: Roadmaster Direct-Connect Base Plate Kit - Removable Arms # RM38VR. These direct-connect base plates...
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  • Is Roadmaster Smart Diode Kit Required for a 2020 Ford Edge ST
    To flat tow your 2020 Ford Edge you will need "smart diodes" as included in the Roadmaster # RO44FR Universal Kit. However, I would go ahead and get the Roadmaster # RM38FR kit that additionally includes the 7-way to 6-way cable and connectors that you will also need. Additionally, your Edge will drain its battery while being towed. I recommend the RM-766 battery disconnect unless you want to manually wrench the battery cables off every time that you unhitch and rehitch! Flat towing...
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    To flat tow your 2020 Chevy Equinox LT with your Roadmaster Tow Bar you'll also need a base plate, tow bar wiring kit, braking system, and safety cables. I have the following recommendations for you below: Base Plate: Roadmaster Direct-Connect Base Plate Kit # RM-523193-5. These direct-connect attachment points allow for easy connection or removal from your tow bar. The removable arms provide a clean factory look when not in use. Tow Bar Wiring Kit: If you have LED tail lights then you'll...
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    In order to use the Roadmaster Nighthawk All Terrain, Non-Binding Tow Bar part # RM-676 on a 2022 Chevrolet TrailBlazer you'll need the Roadmaster Direct-Connect Base Plate Kit part # RM35FR. If you want to use the Roadmaster Nighthawk All Terrain, Non-Binding Tow Bar for Blue Ox Base Plates part # RM-677 you'll instead need the Blue Ox Base Plate Kit part # BLU49FR. The instructions are linked for you so you can determine if you are capable. A few other things you might want to consider...
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    The correct wiring kit will depend on if your 2021 Jeep Gladiator has ParkSense proximity sensors. If you have these sensors you will need the Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights # RM38FR. If you do not have the sensors the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 is the kit you will need. Both kits include a flexible 7-way to 6-way cable, the vehicle side connector and wiring necessary to install the diodes that...
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    Yes, per the online owner's manual I found, your 2020 Chevy Equinox can indeed be flat towed behind a motorhome with all four wheels on the ground. To do so, you're going to need a number of parts, which are the following: - Base Plate Kit: Roadmaster Direct-Connect Base Plate Kit # RM-523193-5 - Tow Bar: Roadmaster Falcon All Terrain, Non-Binding Tow Bar # RM-522 - Safety Chains: RoadMaster 64" Double Hook, Straight Safety Cables # RM-646 - Wiring Kit (For LED Tail Lights): Roadmaster...
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    Image 1 for
  • Parts to Flat Tow 2015 Edge Sport With 2.7L engine and NO Adaptive Cruise Control
    To flat tow your 2015 Edge Sport with 2.7L engine and NO adaptive cruise control you will need the Roadmaster # RM-524444-5 Direct-Connect Base Plate Kit which is well hidden and has simple twist and push/pull installation of connection arms. If you have adaptive cruise control email me back and we will see if there is another alternative. Next you need a tow bar. I recommend the Roadmaster # RM-522 Falcon All Terrain Non-Binding tow bar. A non-binding tow bar will let you easily disconnect...
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  • Compatibility of etrailer SD Tow Bar With etrailer Base Plate On 2021 Jeep Gladiator Plastic Bumper
    Yes, the etrailer SD Non-Binding Tow Bar # e34ZR will fit to the etrailer Invisible Base Plate Kit # e98948 on the front of your 2021 Jeep Gladiator. This base plate fits models with the factory plastic front bumper. You may need a High-Low adapter to keep the tow bars within 3" of level. For wiring you will need either the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 or the Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage LED Tail Lights #...
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Info for this part was:

Employee Lindsey S
Written by:
Lindsey S
Employee Joshua S
Video by:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Mike S
Updated by:
Mike S
Employee Ryan G
Test Fit:
Ryan G

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