How to Run an Electric Jack Off of a Trailer Battery and a 7-Way Connector

Question:

Hello. I am stumped and need some help. I’ll break down my problem. I have an electric trailer jack. I have an onboard battery that stays on my trailer the hole time. Meaning without the trailer being plugged into the truck. The trailer jack still works. But I ran into a problem the other day. The battery went dead on the trailer. When I wired the jack in. I only wired it to just the 12v battery source. But I was thinking. If the battery ever goes dead again. I would like to also have the option of when I plug my 7 way trailer plug in. The electric jack can use the supplied 12v from my truck. But how would I go about wiring it. Meaning I would like wire it where I have the option of powering the electric jack from the battery or the truck. Without having to flick a switch or do any fancy things. Or if I forget the no flip the switch back and I plug my trailer into my truck. Thank you kyle

asked by: Kyle

Expert Reply:

The easiest way to power your electric jack off of the 7-way and/or the battery is to install the Trailer Wiring Junction Box - 7 Terminals item # 3375601100 and connect your jack to the 12v circuit that your battery would also be connected to. This would allow your jack to draw power from both your tow vehicle's 7-way or your trailer's battery.

This inexpensive junction box provides a secure location for all of your 7-way connections. I have linked a review video below so you can see it's features demonstrated.

expert reply by: Jerred H