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Roadmaster Stop Light Switch Kit
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Roadmaster

Roadmaster Stop Light Switch Kit

Part Number: RM-751480
In Stock
$42.78
Retail:$64.09
You Save: 33%
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 RM-751480 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 - RM-751480

Highlights

  • Prevents Costly Brake Damage: Confirms your braking system isn’t pressing the pedal continuously
  • Know When Brakes Engage: Activates your RV’s monitor light whenever your toad’s pedal is applied
  • Protects Tires and Brake System: Ensures the pedal fully retracts after each stop to avoid wear
  • Works Where No Tow Ignition Mode Exists: Keeps your system powered and functional during towing
  • Direct, Reliable Connection: Wires into the fuse box for a constant 12-volt signal to your monitor
Made in USA

Features to know about

Know Your Brakes Are Working: Real Pedal Feedback to Your RV

When you’re towing, it’s not enough to know that a cylinder is moving—you want to know your towed car’s brake pedal is actually being pressed. The Roadmaster Stop Light Switch Kit connects directly to the towed vehicle’s brake light circuit, sending a signal to your RV’s monitoring system every time the pedal is applied. That way, you’ll always know when the brakes are truly engaged instead of just guessing, giving you peace of mind every mile down the road.

Protect Your Vehicle from Brake Damage: Constant Monitoring Prevents Costly Issues

If a supplemental braking system is misaligned or stuck, it can keep pressing on the pedal even when it shouldn’t. That kind of hidden problem can wear out your tires and braking system fast. This kit prevents that by providing a direct signal from the brake pedal itself, showing exactly when the brakes are being applied so you can spot issues right away and avoid expensive repairs.

Works Where Others Don’t: Reliable Power and Direct Wiring

Some vehicles don’t have a “tow” position in the ignition, which can make it hard to get a consistent signal for brake monitoring. This kit solves that by wiring directly into the fuse box for a constant 12-volt current. It ensures steady, reliable operation of your supplemental braking system and your RV’s monitor, no matter your setup.

Simple Confidence Every Time You Tow: Just Works Flawlessly

You don’t have to fuss with complicated electronics or adjustments. Once installed, the Stop Light Switch Kit just works—capturing real brake pedal movement and keeping your system alerting properly trip after trip. It’s one of those small, behind-the-scenes parts that makes the whole towing setup feel solid and dependable.

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.

751480 Road Master Stop Light Switch Kit

Installation Details RM-751480 Installation instructions

This Product Fits The Following Vehicles




Customer Satisfaction Score:

Ratings & Reviews

4.7

710 reviews
5 Stars
(583)
4 Stars
(80)
3 Stars
(29)
2 Stars
(8)
1 Star
(10)
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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:
Doesn't seem to fit 2021 express van. Bracket not long enough. No 13 mm screw
Nick S. profile picture
Etrailer Expert

Nick S.

11/17/2025

Have you checked your owners manual to see if that vehicle is flat towable? I did some digging and I am not finding many parts at all for that vehicle to be able to flat tow it.

by:
What is there to say except the Roadmaster stop light switch kit simply works and works flawlessly.
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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.
Kate F. profile picture
Etrailer Expert

Kate F.

4/23/2026

Thank you for the detailed review and for sticking with the install George. That is a tight space to work in, and we really appreciate you sharing both the challenges and your thought process along the way. You make some very valid points about the alignment sensitivity and adjustability of the switch. I agree, that kind of precision fit without an easy lateral adjustment can make the install more tedious than it should be. It does not make it right, and feedback like this is exactly what helps highlight areas for improvement. It is great to hear that it has been working reliably for you over a few thousand miles so far. Your habit of checking function during hookup is a solid practice and definitely the way to go with setups like this. I will be passing your feedback along to the manufacturer for review, especially your notes on the switch design and mounting adjustability. Also, thank you for including photos even with the tight space. They are very helpful for others tackling the same install.

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
Victoria H. profile picture
Etrailer Expert

Victoria H.

1/14/2025

That's quite impressive Fred, nice ride!

Fred profile picture

Fred

1/8/2026

Everything works just fine! Great product and support! Thanks E-t

Josh B. profile picture
Etrailer Expert

Josh B.

1/8/2026

@Fred thank you for the feedback! The setup is lookin good on your Jeep! Where have you been able to go with your setup?
by:
I couldn’t use the towed vehicle’s brake light circuit on the last two pickups I’ve set up. On the truck before this I robbed a little refrigerator switch that turns on the light when you open the door and rigged up my own. Alas, that wouldn’t work on this newest GMC Canyon. Then I found this device. Wow, what a quick and easy installation. It works perfectly.

I do have a suggestion for ETrailer. Show the actual switch dimensions in your listing. Though the actual switch is quite small, I was worried I wouldn’t be able to make it fit. With nothing but pictures and nothing for scale, it was a concern.
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).
Alan profile picture

Alan

9/8/2026

Its been a year and to be honest, I never have to think about my tow setup. Its there, it works perfect like the day I got it. I cant recommend this any higher. Smooth towing without worrying about it.

Lazer S. profile picture
Etrailer Expert

Lazer S.

9/8/2026

@Alan Glad to hear it's still working well for you! It's definitely nice to not have to worry about the parts you have installed! ^___^ Which braking system did you go with?
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:
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?
Kate F. profile picture
Etrailer Expert

Kate F.

12/17/2025

I wish you could mount it there Donald, but those stop-light-switch studs are only designed to hold the switch bracket. Adding the pulley bracket changes the spacing and alignment, which can make the brake lights stay on, not come on, or throw off the Invisibrake’s operation. The studs also aren’t meant to handle the side-load from the cable, so Roadmaster doesn’t recommend using them. For drilling stainless, the trick is a cobalt bit (M35 or M42), slow speed, steady pressure, and cutting oil so the metal doesn’t work-harden. Are you new to flat towing, or just getting a different vehicle set-up?

Donald R. profile picture

Donald R.

12/18/2025

Thank you for the reply. I have flat towed before, a chevy equinox with RVi brake 3. On my Maverick I don't like how the brake 3 sits against the seat, so decided to upgrade to Invisibrake. Due to the difficulty of drilling behind the brake pedal I would have a hard time giving my recommendations.
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.
Michael R. profile picture

Michael R.

1/18/2024

Still working great

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
Mark S. profile picture

Mark S.

11/3/2025

Its a good choice because its easy in easy out. I have two jeeps that can flat tow, so i was covered for braking in either one

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:
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.
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:
Installed on a 2023 Equinox LT (AWD). I believe there may have been a change to the Equinox brake pedal assembly from prior years. Because of this, I was not able to get the switch located properly with the bracket that is included in the kit. I fashioned my own mounting plate from a piece of diamondplate which I bolted to the brake lever bracketry. This works great and is rock solid.
by:
etrailer’s installation video was very helpful. However, the mounting bracket holes on either end seem to be the same size (the video and instructions state that the switch fits into only one end but for me it fit into both). Consequently, it is not clear which side of the bracket to use for the switch vs the vehicle stud. One other installation hint, perhaps unique to the Wrangler Rubicon or Wranglers with upgraded audio/Uconnect, there is an electronic module (3”x4”), mounted to the dash framework behind the lower dash panel, that must be dismounted in order to allow access to the bracket mounting location (see photo).
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:
Mount was good and directions easy to follow.
by:
Easy installation. I had an issue getting the kit ordered, but the customer service agent was phenomenal in her assistance getting it resolved.
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See what our Experts say about this Roadmaster Flat Tow Brake System

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    GM states in the owner's manual that to recreationally tow the vehicle, the negative battery cable must be disconnected. The owner's manual doesn't list a specific reason, it only states that failure to do so could damage the vehicle. The fact that the key needs to be left in the Accessory position while towing so the steering wheel doesn't lock up gives me a pretty good idea that with the key in the ACC position, there must still be an electrical draw on the battery. Disconnecting the...
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    You've definitely got a great list of parts to flat tow your 2021 Jeep Wrangler so I'll go through each one in order. Baseplate: The etrailer Invisible Base Plate Kit # e98948 is a fit and has removable arms to help keep your Wrangler looking factory. You can use part # DM15675 for some covers so that water doesn't get inside and sit in the baseplate. Braking System: The Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 is a great choice as long as your motorhome has...
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Info for this part was:

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Installed by:
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