Towed Vehicle Battery Charge Line Kit for Demco Air Force One and Stay-IN-Play Duo Braking Systems
Updated 07/09/2026 | Published 07/01/2026
Question:
How does this trickle charge your battery, because it does not actually have a trickle charger on it. All it is doing is putting 12v power to the battery from the coach. Towed Vehicle Battery Charge Line Kit for Demco Air Force One and Stay-IN-Play Duo Braking Systems Part Number: DM66VR
asked by: Brian H
Expert Reply:
Hi Brian,
Thanks for your question, and I apologize for the confusion.
You are correct that the Towed Vehicle Battery Charge Line Kit for Demco Air Force One and Stay-IN-Play Duo Braking Systems # DM66VR is not a trickle charger.
What this kit actually does is help maintain the towed vehicle's battery by providing a 12-volt charge line from the motorhome's electrical system. While you're driving, the motorhome's alternator supplies power through the charge line to the towed vehicle's battery, helping offset the electrical draw from the braking system and other accessories. I think folks use the term trickle and maintain interchangeably here. The motorhome alternator by itself is not going to be able to "charge" a battery from a low or empty state so this is not a traditional battery charger either.
It looks like you may have just gotten a new Jeep Wrangler and are adding some flat tow components. Any big trips planned?
Steve K.
7/8/2026
The charge line setup does work. I wanted more control and added an RVi Towed Vehicle battery charger with dedicated fused feed from motorhome battery. That has battery and state charge status indication and charges as needed.
Product Page this Question was Asked From
Towed Vehicle Battery Charge Line Kit for Demco Air Force One and Stay-IN-Play Duo Braking Systems
- Accessories and Parts
- Flat Tow Brake System
- Wiring
- Battery Charge Line Kit
- Demco
more information >
Continue Researching
- Search Results: battery charger
- Video: Kwikee Electric RV Step Complete Assembly Feature Review
- Shop: Roadmaster Battery Charge Line Kit for Towed Vehicles
- Shop: Towed Vehicle Battery Charge Line Kit for Demco Air Force One and Stay-IN-Play Duo Braking Systems
- Q&A: Rating of Inline Diode on Demco DM66VR Towed Vehicle Charge Line Kit
- Q&A: How to Test Demco Charge Line Kit DM66VR if its Working
- Q&A: Best Battery Charge Line Kit for Flat Towing
- Article: Trailer Wiring Diagrams
- Video: An In-Depth Look at the Roadmaster Battery Charge Line Kit for Towed Vehicles
- Search Results: trailer hitch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Shop: Trailer Hitch
- Shop: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Shop: Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord
- Q&A: Does etrailer Carry Furrion Chill Cube w/ Heat Pump to Replace Dometic Duo-Therm
- Search Results: trailer wiring
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Shop: Trailer Wiring
- Video: An In-Depth Look at the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit
- Shop: Blue Ox Patriot Portable Flat Tow Brake System - Proportional
- Article: How to Measure for Trailer Hitch Drop
- Search Results: trailer tires and wheels
- Shop: Suspension Enhancement
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Shop: Brake Controller
- Video: Curt Class III Trailer Hitch Step-By-Step Install - 2026 Honda CR-V
- Article: How to Choose the Right Trailer Hitch Class
- Search Results: trailer jack
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Q&A: Availability of Heat Strip or Heat Pump for Furrion Chill Cube RV AC
on Accessories and Parts
Sidney
7/8/2026
Just get one. Your toad battery will never be dead after a day of driving.