How to Prevent a 12 Volt Power Circuit on a 7-Way from Being Active All the Time

Question:

I have a pop-up cabover camper that has a 4 pole roundrunning lights/Ground/Hot Lead to deep cycle battery. I would like to get this item and put the 4 pole round plug to keep the deep cycle battery charged while driving but isolate the camper/truck batteries when parked. The 7 pole blade is a Ford factory harness. Please see the photo of the 7 pole plug diagram attached.

asked by: Mike

Expert Reply:

What most people use to allow the 12 volt charge wire from being hot all the time and only when the key or the vehicle is on is an isolation solenoid part # PK5231201 on the charge wire. You basically run the center pin to a keyed power source and then run one side of the solenoid to the 7-way and the other to the wiring of the truck.

If you were wanting to install it on a 4-pole connector that was used strictly for that circuit that is possible too.

This wouldn't work through a 7-way to 4-way adapter though since the circuits of the 4-way would only line up with the taillight functions of a 7-way.

expert reply by: Jameson C