Does Roadmaster Charge Line Kit Have Ability to Overcharge Battery
Updated 02/19/2026 | Published 02/18/2026
Question:
Concerning Roadmaster Battery Charge Line Kit for Towed Vehicles Part Number: RM-156-25. This will detect a fully charged battery and not overcharge?
asked by: Brian S
Expert Reply:
Hey Brian, this is a great question but the Roadmaster charge line kit part # RM-156-25 does not have anything built into it to detect when a battery is fully charged and then stop charging. Now with that said this does not have a high enough amperage or voltage charge that you'd need to worry about that from happening. This is basically just a 10 gauge wire that goes from your tow vehicle battery to your towed vehicle battery and because of that it doesn't have ability to really overcharge a battery. It's going to basically just keep your battery topped off while it's being towed and beyond that you don't really have to worry about it.
What vehicle are you flat towing?
(click to enlarge)
Rick
2/19/2026
Works well I have never had a battery issue after installing it
Tim S.
2/19/2026
Pretty simple install. Used as a precaution. Never towiing it so long that it would even be relevant but nice to have as a backup.
Product Page this Question was Asked From
Roadmaster Battery Charge Line Kit for Towed Vehicles
- Accessories and Parts
- Flat Tow Wiring Harness
- Battery Charge Line Kit
- Roadmaster
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Brian S.
2/18/2026
I am towing a 2025 Bronco.