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Roadmaster Stop Light Switch Kit
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Roadmaster

Roadmaster Stop Light Switch Kit

Part Number: RM78DQ
In Stock
$41.47
Retail:$64.09
You Save: 35%
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 RM78DQ 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 - RM78DQ

Highlights

  • Prevents Costly Brake Damage: Confirms your towed car’s brakes fully release after stopping
  • Know When Brakes Engage: Triggers your RV monitor whenever the toad’s pedal is pressed
  • Confidence in System Setup: Lets you verify your supplemental braking system is working right
  • Works Without Tow Ignition Mode: Ideal for vehicles that lack a dedicated towing position
  • Reliable Power Connection: Wires directly into the fuse box for a constant 12-volt signal
Made in USA

Features to know about

Know Exactly When Your Brakes Engage: Direct Pedal Monitoring

When you’re towing, it’s important to know what’s really happening with your brakes—not just that a system is trying to activate. This stop light switch kit wires directly into the towed car’s fuse box for a constant 12-volt current and triggers your RV’s brake-monitoring system whenever the brake pedal is actually pressed. That means you see what’s really going on with the pedal itself, not just the air cylinder or actuator, giving you a clear and accurate signal every time.

Protects Your Vehicle from Hidden Brake Damage

A misaligned supplemental braking system can keep pressure on the pedal even when you’re not braking. That can cause drag, tire wear, or even damage to the braking system. By letting you know whenever the pedal is being depressed, this kit helps you catch setup issues before they lead to costly repairs. It’s a small safeguard that can make a big difference in keeping everything working right.

Keeps You Covered When There’s No Tow Mode

Some vehicles don’t have a tow position in the ignition, which can make it tricky to monitor the brakes correctly. This kit solves that by giving you a direct signal from the pedal, so the system still works properly even when there’s no dedicated tow mode. It’s a simple, reliable way to make sure your supplemental braking system always communicates exactly when your towed car’s brakes are engaged.

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.

751519 Road Master Stop Light Switch Kit

Installation Details RM78DQ Installation instructions

This Product Fits The Following Vehicles




Video of Roadmaster Stop Light Switch Kit
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Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Review of Roadmaster Flat Tow Brake System - Stop Light Switch kit - RM78DQ

Hi, everyone. Steve here with etrailer.com. Today we're looking at this Roadmaster Stoplight Switch Kit. Now folks, this is a custom fit application, so be sure you're double checking the fit guide here at etrailer.com on our homepage where it says, "My vehicle information," enter things like year, make and model, bed lengths, cab lengths, whatever it's asking you to be sure you get the right parts the first time. Now, what this is gonna do, this stoplight switch kit, it's gonna activate the motor home brake monitoring system whenever that brake pedal in the towed car is applied. It's gonna ensure that the supplemental braking system is functioning correctly and it's gonna work great for any application that does not have a tow position in the ignition.

So this will wire directly into the car's fuse box for constant current. It is running on 12 volts and you've got the little fuse box tapper here an inline fuse, some butt connectors, couple of wires, color coded, and then obviously the stoplight switch and you've got the bracket here, the custom bracket. Well, that's gonna wrap it up for our quick look together. I'm Steven, thanks for watching.

Ratings & Reviews

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


Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Steven C
Installed by:
Steven C
Employee Wilson B
Updated by:
Wilson B
Employee Amanda K
Written by:
Amanda K

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