Diode Recommendation to Prevent Trailer Battery From Backfeeding onto Vehicle Wiring

Updated 06/15/2018 | Published 06/14/2018

Question:

Im not sure if this is the correct item for what I want to do. I want to install a battery in my cargo trailer to power the interior lights. My plan is to locate and cut the constant 12 volt from my vehicle and attach it to one side of the solenoid. Then attach the other wire to the other side of the solenoid. Them I will attach the positive from my new trailer battery to the third side of the solenoid. Does this sound correct? I dont want the trailer battery to back feed my vehicle.

asked by: John R

Expert Reply:

If all you want is to prevent the 12 volt power supply of your trailer battery wiring from backfeeding onto your vehicle wiring or vice versa what you need is a one-way diode like part # RM-690. This only allows current to flow in one direction so you'd just need to install it inline with your trailer wiring matching the in and outside to your setup and you'd be good.

expert reply by: Jameson C