Hi. I have a question about battery charging on my 2009 X139. When I am hooked to 110 volts my battery charges fine. I also have a 12 volts coming out of my 2009 Ram pickup that goes straight to the X139 battery. The 12 volts from the truck is only hot when the truck is running. I have been reading online and getting conflicting information. Will the tow vehicle be able to keep the battery at its top charge? Will it overcharge? Do I need a special circuit in the line to make the trailer battery charge properly and to protect it? Does the X139 have a charging circuit built into it that accept the 12 volts from the tow vehicle? I want the proper charge for the electric brakes. Thanks.
The wire from your truck is not very big. Maybe 16 awg at most. It wont carry enough current to really charge your battery. It will provide enough current to keep a small battery charged for brake power if the trailer separates from the tow vehicle.
If you really want to charge the battery run a 10 or 12 AWG wire and install something like this. https://www.wirthco.com/20090.html there are others this is just one type
X139 Battery Charging From Tow Vehicle
Linear Mode
