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  1. Flat Tow Wiring Harness
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  3. Grand Cherokee
  4. 2021
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FITS 2021 Jeep Grand Cherokee
Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Hybrid Adapter Cord
Roadmaster

Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Hybrid Adapter Cord

$229.59
Flat Tow Wiring Harness
Confirmed to Fit
2021 Jeep Grand Cherokee

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Call etrailer.com at 1-800-940-8924 for expert service. We are your Jeep flat tow wiring harness experts, and offer a great price. etrailer.com carries a complete line of Roadmaster products for your Jeep Grand Cherokee 2021. Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Hybrid Adapter Cord part RM-152-1676-7 from Roadmaster can be ordered online at etrailer.com. Complete flat tow wiring harness installation instructions and technical support.
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2021 Jeep Grand Cherokee - Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Hybrid Adapter Cord

  • Diode Kit
  • Splices into Vehicle Wiring
  • Universal
  • Roadmaster
  • 30 Foot Long Harness

This complete kit includes everything you need to carry your RV's brake and turn signals to your towed car's tail lights. Diodes prevent electrical feedback. The hybrid coiled/straight adapter cord is ideal for tow bars with channel guides.


Features:

  • Carries your RV's tail, brake, and turn signals to your towed car
  • Prevents feedback that can damage your car's electrical components
  • Runs power from RV to towed car with 7-wire to 6-wire adapter cord
    • Straight/coiled hybrid cable is ideal for tow bars with channel guides, such as Roadmaster all-terrain tow bars
    • 6-Way socket wires to harness and mounts on front of towed car with included bracket
  • Includes:
    • 4 Hy-Power diodes
    • 4-Wire harness
    • 7-Way to 6-way hybrid adapter cord
    • 6-Way socket with mounting bracket
    • Butt connector, ring terminal, zip ties, and wire loom
  • Limited lifetime warranty


Specs:

  • Maximum amperage: 85 amps
  • Maximum voltage: 24 volts
  • Adapter cord: 8' long
    • Wire gauge: 16
  • Wiring harness: 30' 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 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 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 your towed car's brake lights illuminate when you press the brake pedal with the engine off, 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


152 Road Master Universal Hy-Power Diode Wiring Kit

1676-7 Road Master Coiled-to-Straight 7- to 6-Wire 8' Power Cord

910030-5 Electrical Socket Bent Bracket - Roadmaster

910030-7 RoadMaster 6-Wire Trailer Connector - Volkswagen Vanagon End

Item # RM-152-1676-7

Installation Details RM-152-1676-7 Installation instructions

California residents: click here


Customer Satisfaction Score:

Ratings & Reviews

4.8

2909 reviews
5 Stars
(2510)
4 Stars
(274)
3 Stars
(59)
2 Stars
(22)
1 Star
(44)
This complete kit includes everything you need to carry your RV's brake and turn signals to your towed car's tail lights. Diodes prevent electrical feedback. The hybrid coiled/straight adapter cord is ideal for tow bars with channel guides.

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2909
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See what our Experts say about this Roadmaster Flat Tow Wiring Harness

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    view full answer...
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