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RoadMaster Stop Light Switch Kit
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Roadmaster

RoadMaster Stop Light Switch Kit

Part Number: RM77RR
In Stock
$53.78
Retail:$69.99
You Save: 23%
Flat Tow Brake System
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Avoid damage to your vehicle by ensuring that your supplemental braking system is properly positioned and working effectively. Kit activates your RV monitoring system to alert you when the brakes of your towed car are being applied. 1-800-940-8924 to order Roadmaster flat tow brake system part number RM77RR or order online at etrailer.com. Free expert support on all Roadmaster products. Great prices and Fastest Shipping for RoadMaster Stop Light Switch Kit. Flat Tow Brake System reviews from real customers.
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Roadmaster Flat Tow Brake System - RM77RR

Highlights

  • Know When Brakes Engage: Activates your RV’s monitor whenever the towed car’s pedal is pressed
  • Protects Your Vehicle: Confirms your supplemental braking system isn’t applying constant pressure
  • Prevents Costly Damage: Helps avoid tire and brake wear from a misadjusted braking setup
  • Always Connected Power: Wires to the car’s fuse box for a steady 12-volt current
  • Works Without Tow-Ignition Mode: Ideal for vehicles lacking a tow position in the ignition
Made in USA

Features to know about

Always Know When the Brakes Are Applied: Direct Signal to Your RV Monitor

When you’re towing, you want to know your braking system is actually working. This Stop Light Switch Kit activates your RV’s brake-monitoring system whenever the towed vehicle’s brake pedal is pressed. Unlike systems that only sense cylinder movement, this one monitors the pedal itself. That means you get a true reading of what’s happening, giving you confidence that your supplemental braking system is doing its job.

Prevents Costly Damage: Confirms Proper Braking Operation

A misaligned or constantly engaged braking system can cause serious wear or tire damage. By wiring directly into the fuse box for a constant 12-volt current, this kit ensures your supplemental braking setup isn’t pressing on the pedal when it shouldn’t be. You’ll know right away if something’s off before it leads to expensive repairs.

Works Where Standard Circuits Don’t: Reliable Power for Any Setup

Some vehicles don’t have a traditional stop light switch circuit or a dedicated towing ignition position. This kit solves that by providing its own independent switch that connects directly to the brake pedal. It delivers a clean, consistent 12-volt signal so your RV’s monitor can read real braking activity even when factory wiring doesn’t provide a usable circuit.

Simple, Solid Connection: Custom Fit and Direct Integration

Built as a custom-fit kit for your specific vehicle, it installs cleanly and ties right into the fuse box to deliver accurate, real-time feedback. Once in place, it becomes a dependable part of your flat-tow setup, giving you a clear indication of braking each time you tow.

Specs

Electrical

  • Voltage: 12 Volts

Application

  • Fit: Custom fit for your vehicle

What You Need to Flat Tow

Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up.


To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.


For the RV Between the RV and Towed Car For the Towed Car
Hitch Tow bar Base plate
Wiring plug Safety cables Braking system
Wiring adapter cord Wiring kit/diodes

The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome.

751507 Road Master Stop Light Switch Kit

Installation Details RM77RR Installation instructions

This Product Fits The Following Vehicles




Customer Satisfaction Score:

Ratings & Reviews

4.7

701 reviews
Review sort icon
Avoid damage to your vehicle by ensuring that your supplemental braking system is properly positioned and working effectively. Kit activates your RV monitoring system to alert you when the brakes of your towed car are being applied.

by:

Easy installation. I had an issue getting the kit ordered, but the customer service agent was phenomenal in her assistance getting it resolved.



by:

It works as designed. Tricky for this old fat guy to work under the jeep dash but eventually got it installed and adjusted.



by:

Was disappointed that your site said this was the part I needed so I ordered it. Then realized it was not correct part. Called next day to cancel and Oder correct part. I was told I could not cancel it and would have to pay to ship it back. The correct part which was ordered second came 2 days before first part. To get a refund I still had to pay to ship it back. Other than this trailer has been good to work with and quality parts.



by:

Easy installation. Fit perfectly in my 2014 Grand Cherokee.



by:

Works great fairly easy install. It has been in use for the last 8 month's with no issues. Here may be some helpful hints that I found when installing. Use 10-12" long extension for 13mm nut (left side of opening panel that was removed). Install bracket. Adjust plunger & backing nut by feel. Remove bracket. Install switch with ring washer & nut. Crimp red & green wires on switch wires. Reinstall bracket under dash.



by:

Ill give it 3 stars because I had to shim the bracket to make the plunger line up with the brake arm. But it works well so far.



by:

It is my opinion that the universal brake light switch is the easy way to go. Hardest part doing the DIY way is the place you are working in. I.have a few sore spots trying to get underneath the steering wheel. The benefit is you have instant info that the switch works. A light comes on when you push the break pedal



by:

Roadmaster products are great, very pleased with the superb instructions. Very difficult to mount the pulley for the invisibrake in my Ford Maverick. Trying to drill stainless steel behind the brake pedal was near impossible. Could a bracket for the pulley be mounted on the same studs as the Stop Light Switch?



by:

I have a ‘23 Bronco with the Lux package. The Bronco had a factory brake switch in the spot this thing would go. Advice was unclear whether I could use a factory wire to install my brake controller. I went with the wire that lit the test light when brakes were pressed (key on). I think it was violet with a stripe at the plug for a factory Brake controller. I don’t have the factory tow package. Seems to work but not yet tested with a trailer. Only 3 stars because of the uncertainty. I’ll use this switch on a different project.



by:

Product works great...But was shorted the female connector to terminal 1...Cost over 5 dollars at Auto Zone.As no one sells just one.....Its in the picture...Not in my parts bag...But a perfect fit on the brake switch mount .Three stars only because I had to go buy a connector to complete the job.



by:

One year later and I haven't had to touch this system even once. It just works, all the time, every time. Very happy with this kit. Works perfectly in my 2019 Toad (Jeep Cherokee).



by:

I installed the item in my 2024 Bronco to support braking indication in the motorhome while being towed, since Ford does not include one these days. As far as I can tell, this is the only commercially available kit to avoid cobbling up your own design. It is tedious to install mechanically and, especially tedious to adjust transverse mount position and depth of travel. The button on the switch is too small, requiring very precise alignment to the brake pedal arm (approx 1/4" wide) in the transverse direction from the switch movement. There is no screw type adjustment in that direction so bracket bending/and or bracket mounting spacers is required. I am also afraid the switch button being small and made of some type of poly, it will slip sideways, deform, or wear with even the slightest offset and begin to push the bracket aside. However, it has worked in a few thousand miles of towing behind a motorhome so far. I will keep an eye on this and test function whenever hooking up to tow (a normal practice anyway). I kept thinking it would be easier to use a long lever low force microswitch instead of a tiny soft-tipped, rather hard spring or drag, pushbutton, which would require its own mounting design. Maybe a small highly adjustable ball clamp mount work with a microswitch as well. But I must resist my engineering background tendencies in exchange for getting the job done! Sorry for the quality of the photos. It is in a difficult place for phone camera.



by:

Thanks everyone at etrailer for your help and quick response and shipping! My project turned out really great as you can see in the pictures I have included. The plug for the removable holders I 3D printed. Thanks Fred



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Katrina B. profile picture

Katrina B.

10/25/2022

I see that you gave your experience with etrailer 1 star. If you give me more information about why you are disappointed in us, I will be happy to assist you.



by:

Thank you, order arrived as promised, and install was easy and fit my 2025 Jeep Grand Cherokee Overland perfect to operate my brake light on my Motorhome dash.


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See what our Experts say about this Roadmaster Flat Tow Brake System

  • Recommended Baseplate For A 2023 Jeep Grand Cherokee 4xe With Roadmaster Falcon 5250 Tow Bar
    Hey Michael, The Falcon 5250 has direct-connect attachment points that hook onto a crossbar, if you remove the crossbar adapter then you'll be able to go with a direct-connect baseplate like the # RM77ZR (models with tow hooks) or # RM76RR (models without tow hooks). If you haven't picked out the rest of your setup then I have the following recommendations: Tow Bar Wiring Kit: Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267. This diode kit will splice into your factory...
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  • Complete Flat Towing Setup for a 2023 Jeep Grand Cherokee Overland W/ Tow Hooks
    I would personally go with Roadmaster's stuff. They've had a really good track record in my experience and have been an industry favorite for a while. So, for your 2023 Jeep Grand Cherokee you're going to want the Roadmaster Direct-Connect Base Plate Kit # RM77ZR for a base plate and the Roadmaster Nighhawk # RM-676 for a tow bar. This tow bar will easily attach to the base plate using the direct connect brackets, has an integrated LED light for low light conditions, and has an 8K capacity...
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  • What Base Plate and Wiring do I Need to Flat Tow My 2025 Jeep Grand Cherokee L Summit?
    Hello Ovi, Happy to help clear things up for you! Starting with the base plate, you are correct. The Demco Tabless Base Plate Kit with Removable Arms # DM46GV is a great fit for your 2025 Jeep Grand Cherokee L Summit, since your vehicle does not have the lower active shutter. This allows for a clean installation with removable arms when you’re not towing. For the wiring you will indeed want to use the Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled...
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  • Parts Needed to Flat Tow 2023 Jeep Cherokee L Overland
    In order to flat tow your 2023 Jeep Grand Cherokee L you will need the following: -Base Plate: Roadmaster Direct-Connect Base Plate Kit # RM77ZR -Tow Bar: Roadmaster Nighthawk All Terrain, Non-Binding Tow Bar w/ LED Lights # RM-676 (this includes safety cables) -Tow Bar Wiring: Roadmaster Universal Hy-Power Diode Wiring Kit # RM-154 -Supplemental Braking: Brake Buddy Select 3 Portable Supplemental Braking System # HM39524. This system comes with a charge line kit included to keep your...
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  • Parts Needed to Flat Tow 2023 Jeep Grand Cherokee
    Hey Craig! It looks like you got most of the parts already. I see you ordered the following: -Roadmaster Direct-Connect Base Plate Kit # RM77ZR -Roadmaster Nighthawk All-Terrain Tow Bar # RM-676 -Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles # RM-15267 -Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 -Roadmaster InvisiBrake Flat Tow Brake System # RM-8700 The base plate kit is designed for the Overland with the front tow hooks and no active grill shutter....
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  • Recommended Flat Towing Components For A 2024 Jeep Grand Cherokee Overland
    Hey Dave, I have the following flat towing component recommendations for your 2024 Jeep Grand Cherokee Overland: Baseplate: Roadmaster Direct-Connect Base Plate Kit # RM77ZR. Tow Bar: etrailer XHD Non-Binding Tow Bar # e84ZR. This tow bar comes with safety cables bracketed to the arms so that you don't have to purchase them separately or worry about them dragging. The head/shank has a built in drop/rise to help keep the tow bar level without also purchasing a high/low adapter. There's...
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  • Parts Needed to Add a Brake Controller for a 2022 Jeep Grand Cherokee L
    Hey Salman, so since your Jeep does not have a traditional stop light switch circuit, you'd need to use the RoadMaster Stop Light Switch Kit # RM77RR. If you didn't want to use that, then you could also use a wireless brake controller like the Curt Echo # C51180 which just gets installed in your 7-way.
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  • Roadmaster Base Plate To Use with 2024 Jeep Grand Cherokee Overland
    Hey Philip, the correct Roadmaster base plate kit you'd need is the part # RM77ZR for your 2024 Jeep Grand Cherokee L to use with your Roadmaster Nighthawk # RM-676. Then with the Roadmaster Invisi Brke part # RM-8700 you'd also need the stop light switch part # RM77RR and you'd be set. How do you like the Nighthawk?
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  • Recommended Flat Towing Components For A 2023 Jeep Grand Cherokee L Overland
    Hey Joe, I have the following component recommendations for your 2023 Jeep Grand Cherokee L Overland: Baseplate: Blue Ox Base Plate Kit # BLU68CR Tow Bar: Blue Ox Avail Non-Binding Tow Bar # BX7420, This will also include safety cables so you won't have to purchase them separately. Tow Bar Wiring Kit: Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267. This will splice into your factory wiring to display your motorhome's traffic signals through the tail lights of the...
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  • Where is the Stop Light Switch Wire on a 2023 Jeep Grand Cherokee L
    I do have an option for you but there isn't a traditional stop light switch circuit on a 2023 Jeep Grand Cherokee L. Therefore, if you want to use a wired trailer brake controller you'd need a stop light switch like the RoadMaster Stop Light Switch Kit part # RM77RR. The other option would be a wireless trailer brake controller like the Curt Echo Wireless Brake Controller part # C51180 which does not require a stop light switch connection.
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  • Complete Flat Tow Set Up For 2025 Jeep Grand Cherokee Summit Reserve
    Hello Teresa! Congrats on the new Jeep! Here is a list of parts you will need to flat tow it behind your RV. -Base Plate Kit: If you 2025 Jeep Grand Cherokee does NOT have lower air shutters: Roadmaster Direct-Connect Base Plate Kit - Removable Arms # RM76RR If you 2025 Jeep Grand Cherokee DOES have lower air shutters: Roadmaster Direct-Connect Base Plate Kit - Removable Arms # RM75GR. -Tow Bar: Roadmaster Nighthawk All-Terrain Tow Bar w/ LED Lights - Non-Binding - RV Mount - 8,000...
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  • Tow Bar Wiring Kit Needed For Flat Towing A 2023 Jeep Grand Cherokee Summit
    The brake light switch wire for your 2023 Jeep Grand Cherokee Summit isn't useable so you wouldn't be able to install a brake light relay kit any way. In cases like this the turn signal will override the brake signal until the computer inside the Jeep "goes to sleep" after about 20 minutes. The general guideline is to just get all hooked up and running and let it idle for 20 minutes but gas isn't cheap so most people just take off and let it go to sleep while already towing. Since you...
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    I've listed out the parts you'll need to flat tow your 2023 Jeep Grand Cherokee Summit below but you'll want to also check with your local dealer for wiring harness information if your vehicle needs the MOPAR RV towing wiring harness kit #82216418AA. Baseplate: Roadmaster Direct-Connect Base Plate Kit # RM76RR. This is confirmed by Roadmaster to fit Summit models. Tow Bar: etrailer SD Non-Binding Tow Bar for Roadmaster Direct-Connect Base Plates # e74ZR. This tow bar comes with safety...
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    There is a Blue Ox flat tow set up for your 2023 Jeep Grand Cherokee WL (the new body style) with tow hooks. Here are the parts you'll need, which I verified with Blue Ox: - Base Plate: Blue Ox Base Plate Kit # BLU68CR - Tow Bar: Blue Ox Alpha 2 Non-Binding Tow Bar # BX7380 - Wiring Kit: Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 - RoadMaster Stop Light Switch Kit # RM77RR - Towed Vehicle Battery Charge Wire Kit for Demco Supplemental Braking Systems # DM66VR -...
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  • Recommended Brake Controller For A 2022 Jeep Grand Cherokee Trailhawk 4xe
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  • Best Flat Tow Set-Up For 2022 Jeep Grand Cherokee L Overland Model W/ 5.7 Hemi
    You are looking at five primary components for a safe flat towing setup. These are (1) Base Plates (2) Tow Bar (3) Safety Cables (4) an Electrical Wiring solution (5) a Supplemental Braking set-up My recommendations are: - Base Plate, # RM77ZR This is a direct-connect type base plate that will work with multiple Roadmaster tow bar options. - Tow Bar, # RM-676 (safety cables are included so no additional cost for those) The Roadmaster Nighthawk All Terrain, Non-Binding Tow Bar w/ LED...
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    Yes, the Roadmaster Direct-Connect Base Plate Kit - Removable Arms # RM76RR will fit your 2022 Jeep Grand Cherokee 4xe. To complete your setup with Roadmaster, I recommend the: -Roadmaster Nighthawk All Terrain, Non-Binding Tow Bar w/ LED Lights # RM-676 for a set of tow bars. This tow bar is going to be compatible with the Roadmaster Direct-Connect # RM76RR base plate mentioned above, has a maximum weight capacity of 8,000-lbs, and has an integrated LED strip for low-light conditions. -For...
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  • What Powers The Diodes In A Diode Wiring Kit
    The diode wiring isn't going to be wired in series so you won't have to worry about the voltage increasing. It will only be powered by the 7-way of your motorhome when the brakes or the turn signals are activated on the motorhome. I've attached a video below where Ryan will walk you through the installation of your diode wiring. Since your 2022 Jeep Grand Cherokee has combined wiring and an unusable brake light switch wire you'll need the Roadmaster Stop Light Switch Kit # RM-751449 (WK...
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Do you have a question about this Flat Tow Brake System?


Info for this part was:

Employee Lindsey S
Written by:
Lindsey S
Employee Joshua S
Video Edited:
Joshua S
Employee Dustin K
Video Edited:
Dustin K
Employee Chris R
Video Edited:
Chris R
Employee Wilson B
Updated by:
Wilson B
Employee Ryan G
Test Fit:
Ryan G
Employee Bradley B
Test Fit:
Bradley B
Employee Scott A
Test Fit:
Scott A
Employee Andy C
Installed by:
Andy C
Employee Ethan H
Video by:
Ethan H
Employee Joshua U
Video by:
Joshua U

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