Brake Light Relay to Prevent Motorhome Turn Signals Being Overridden By Brake Lamp on Towed Vehicle
Updated 03/03/2015 | Published 03/02/2015 >
Products Featured in This Question
Question:
I am adding the Hopkins tail light Isolating diode system #38955 on my 2005 Pontiac G6 and will be using a Brake Buddy supplemental brake system. When the Brake Buddy applies the brakes, the brake lights on the car are illuminated and at the same time the motor home lights will also illuminate the brake lights. Will this harm either the diodes or the brake lights? Would it be best to remove the fuse for the brake lights while towing?
asked by: Bob B
Expert Reply:
You'll need to install a Roadmaster Brake Light Relay, part # RM-88400. The purpose of a brake light relay kit is to prevent your towed car's brake signal from overriding the turn signal that comes from your RV. When your towed vehicle is properly wired and connected to your RV, its indicator lights will illuminate as you engage the turn signals in your RV. However, if you have only a four-diode system in place, the turn signal will be overridden by your towed car's brake signal as soon as your supplemental braking system presses the towed car's brake pedal. As a result, drivers behind you know only that you're slowing down and not that you are turning. It's not going to harm anything on the vehicle, but the taillights won't be working properly.
Installing a brake light relay in your towed vehicle fixes this problem by ensuring that your car's brake signal does not override the RV's turn signal. Therefore, your towed car's lights will function in accordance with your RV at all times.
The bottom of the product description page has a diagram showing how the relay would install.
Featured Help Information
Miscellaneous Media
Continue Researching
- Shop: Vehicle Tow Bar Wiring
- Q&A: Do Any Flat Tow Wiring Kits Plug Into 7-Way at Back of 2011 Chevy Tahoe
- Article: How to Choose a High-Low Adapter
- Article: How Level Should a Tow Bar Be When Flat Towing
- Shop: Base Plate for Tow Bar
- Shop: Vehicle Tow Bar Brake System
- Video: All About the Hopkins Custom Tail Light Wiring Kit for Towed Vehicles
- Video: Install: Roadmaster Brake-Lite Relay Kit for Towed Vehicles on a 2022 Ford Ranger
- Video: An In-Depth Look at the Roadmaster Battery Charge Line Kit for Towed Vehicles
- Video: Choosing the Right Tow Bar Wiring
- Video: Breaking Down the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit
- Shop: etrailer XHD Non-Binding Tow Bar - RV Mount - 2" Hitch - 10,500 lbs
- Shop: Demco Trailer Connector Adapter - 7-Way to 4-Way - 7' Cord
- Shop: Roadmaster Brake-Lite Relay Kit for Towed Vehicles
- Shop: Curt Tow Bar 7-Way to 6-Way Coiled Adapter Cord w/ 6-Way Socket - 7' Long
- Shop: Roadmaster Nighthawk All-Terrain Tow Bar w/ LED Lights - Non-Binding - RV Mount - 8,000 lbs
- Shop: Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord
- Shop: Curt Tow Bar 7-Way to 4-Way Coiled Adapter Cord w/ 4-Way Round Socket - 8' Long
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Search Results: trailer hitch
- Shop: Trailer Hitch
- Article: Trailer Wiring Diagrams
- Search Results: trailer wiring
- Video: An In-Depth Look at the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit
- Shop: Trailer Wiring
- Q&A: Which is Better Roadmaster or Blue Ox Tow Bar
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Video: Comparing Portable Flat Tow Braking Systems - Curt RVi and Blue Ox Patriot
- Article: How to Measure for Trailer Hitch Drop
- Search Results: base plate for tow bar

