Power for Brake Buddy and Charging Battery on Towed Vehicle

Question:

I purchased the a diode kit, brake relay, brake buddy 3, and the other parts recommended to flat tow my 2019 ranger. In the diode kit installation video, there is no setup of a line to keep the ranger battery charged. The brake buddy has a 15v battery charging wire set. What is the best way to setup battery charging for the ranger? I am thinking using the brake buddy included parts is best. Which port of the 6 wire electrical socket should it be installed in? There are 4 wires in the bundle, leaving two wire ports open. Is the center auxiliary port the one I need to use for the battery charge line?

asked by: Trevin L

Expert Reply:

The Brake Buddy # HM39524 "Select 3" instructions (available at their website) say to not use the 12-volt accessory outlet (the old cigarette lighter outlet) but to rather use the included wiring harness (with included in-line 15 amp fuse) to connect directly to your towed car's battery.

I would additionally use the Roadmaster # RM-156-25 Battery Charge Line Kit. This connects to the 12-volt accessory connection on the back of your 6-way connector at the front of your towed vehicle to your towed vehicles battery to keep it charged while towing. This kit included wiring and a resettable fuse.

I have attached a link showing the wiring pin out for standard 6-way connectors.

expert reply by: Les D