How to Charge a Trailer Battery from a Tow Vehicle
Trailer batteries charge from a tow vehicle through a 7-pin or 6-pin connector,
How Does a Trailer Battery Charge While Towing?
Short Answer: A trailer battery charges while towing through the vehicle's 7-pin connector,
How Does a Tow Vehicle Charge Your Trailer Battery
Short Answer: Yes, most tow vehicles charge trailer batteries through a 7-pin connector