Is a Diode Needed to Prevent Backfeeding from Trailer to Tow Vehicle
Question:
What size diode is needed in the charging line from the tow vehicle to protect the tow vehicle electrical system? Is it possible for a back feed from the winch and brake away battery to damage the tow vehicle electrical system, in the event the emergency break away power is activated by the break away switch while towing?. A local brake control installer mentioned this could happen but I have not thought to much about it until lately. I do not think by tow vehicle is charging my trailer battery while towing. Sounds like a good idea to keep the battery up on the road.
asked by: Steve
Expert Reply:
There is a possibility of back feeding but this should not really be of a concern as the odds of it happening are slim to none. If you did choose to use a diode then you would need one rated for the components it would be powering. The highest rated diode we carry is the Roadmaster Single Park Light Diode part # RM-690 which is rated at 85 amps.
There are a few things you will need to take into consideration for your winch and breakaway system. For starters, it is not advised to run both a breakaway switch and winch off of the same battery. A breakaway switch like part # 50-85-313 should always be connected to a 5-amp hour battery. This battery should not be used to power or charge any other circuits.
The winch can then be either hooked up to a separate auxiliary battery on the trailer or ran directly to the tow vehicle with a wiring kit like the Bulldog Winch Rear Wiring Kit part # BDW20206. If you will be using an auxiliary battery on the trailer to power the winch then you will need to use a battery charger like the Redarc BCDC Dual Battery Charger part # 331-BCDC1240D.
The 12 volt power coming from the vehicle's 7-way trailer connector can then be ran to the breakaway battery and auxiliary battery to maintain their charge. This charge line should not be used to charge a winch battery as it would be far too underrated. I have attached our " How to Wire an Electric Winch" help article for you as well.
Products Referenced in This Question
Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp
- Battery Charger
- Battery Charger
- RV/Camper
- Trailer
- 200 Ah
- Charges/Maintains
- 12V
- Solar Panels to Auxiliary Battery
- Vehicle Battery to Auxiliary Battery
- Redarc
more information >
Bulldog Winch Rear Wiring Kit - Quick Connect to Terminal End - 2 Gauge - 20' Long
- Accessories and Parts
- Electric Winch
- Wiring
- Quick Connects
- Wiring Kits
- 20 Feet Long
- 2 Gauge Wire
- Bulldog Winch
more information >
Roadmaster Single Park Light Diode
- Accessories and Parts
- Tow Bar Wiring
- Diodes
- Roadmaster
more information >
Product Page this Question was Asked From
Tekonsha Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger - Top Load
- Trailer Breakaway Kit
- Kit with Charger
- Top Load
- Single-axle
- Tandem-axle
- Triple-axle
- LED Tester
- Tekonsha
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Vehicle Tow Bar Wiring
- Shop: Roadmaster Single Park Light Diode
- Shop: etrailer Electric Trailer Brakes - 10" - Left/Right Hand Assemblies - 3,500 lbs
- Shop: 7-Way Molded Trailer Wire Connector, 4' Long
- Article: Diode Installation Instructions for a Dinghy with Separate Tail Light Wiring
- Q&A: Can a Diode be Used to Prevent Back Feeding from a Trailer Breakaway Battery to a Brake Controller
- Search Results: diode
- Search Results: wiring diodes
- Search Results: brake light diode
- Search Results: 12v diode
- Search Results: diode kit
- Shop: Easy Grease Trailer Hub and Drum Assembly for 3.5K Axles - 10" - 5 on 4-1/2 - Pre-Greased
- Shop: Deka Bonded 3 Wire - 18 Gauge - Per Foot
- Shop: Dexter Trailer Hub & Drum Assembly for 3,500-lb Axles - 10" Diameter - 5 on 4-1/2 - Pre-Greased
- Shop: Roadmaster Battery Charge Line Kit for Towed Vehicles
- Shop: Base Plate for Tow Bar
- Shop: Trailer Wiring
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Shop: Suspension Enhancement
- Video: Best 2016 Ford Edge Trailer Wiring Options
- Video: Roadmaster EZ5 Base Plate Kit Installation - 2017 Ford Edge
- Q&A: Diode Recommendation to Prevent Trailer Battery From Backfeeding onto Vehicle Wiring
- Article: Trailer Wiring Diagrams
- Search Results: electric drum brakes
- Video: Firestone Coil-Rite Air Helper Springs Installation - 2012 Toyota 4Runner
- Search Results: bearings
- Video: Hopkins Custom Fit Vehicle Wiring - Trailer Hitch Wiring - HM11140484 Review
- Shop: Vehicle Tow Bar Brake System
- Video: Roadmaster Single Park Light Diode Installation - 2012 Jeep Grand Cherokee
- Q&A: Can Roadmaster Diodes part # RM-690 be Used on Tow Vehicle Wiring
on Trailer Breakaway Kit
