Can Lights, Jack, and Winch be Powered by 12V Circuit Coming From Tow Vehicle

Updated 08/12/2014 | Published 08/10/2014

Question:

PK5231201 can i put this on the trailer with the 7 pin power lead connected to both battery and 12V, with the outout connected to the battery circuit on the trailer? The trailer has a 120V battery charger. I want to be able to power the 12V lights, winch and Husky trailer jack from the running vehicle if the trailer battery is dead. thanks

asked by: Jeff G

Expert Reply:

The function of the Battery Isolation Solenoid, # PK5231201, is to shut off the 12-volt feed from your vehicle battery to 12-volt accessories on your trailer when the ignition is turned off. This lets you run the trailer's electrical components without draining your vehicle's battery, assuming that you have a trailer mounted battery. The isolation solenoid is designed to be mounted on the tow vehicle because it requires an ignition switched power source in order to function. By using this solenoid, your vehicle would have to be running in order to be able to pull power from your vehicle's battery.

Technically, you can power your 12-volt lights and Husky trailer jack from the 12-volt circuit coming from the tow vehicle but most electric jack manufacturers do not recommend doing so.

Since a winch typically requires heavier gauge wire, powering the winch from the vehicle's 12-volt circuit is not recommended because it could burn the wire and cause a short.

If you still choose to use the 12-volt circuit on your vehicle as a backup power source to power the lights and jack on your trailer, you would just need to run the 12-volt power wire from the 7 way on your trailer to the positive post on the trailer battery. As long as the 7 way on your trailer is plugged into the 7 way on your tow vehicle, you will be able to power your accessories.

expert reply by: Leah S