Originally Posted by jhayesas
The below image illistrates the white wire and what I’m working with.
The below is temporary and used for testing until the other wires comes in today.
It appears that the "white"wire was perhaps something that someone added. The tell tale sign is the homemade crimping job. I'm not sure what it is for. You would have to trace it back. In DC circuits black is typically negative and red is positive. In AC it is black is hot and white is neutral. Ground is always green or bare copper. Now you do get some companies that use brown and blue in DC circuits, but that is mostly for electrical cabinet wiring. At work we will even have the wire custom painted to match certain specs. The white wire could also be a sense line to a controller, but without tracing it back it I cannot tell for sure. The white wire was connected to the ground lug so I would leave it there. All you want to do is connect a short piece of new wire (1/0) from the ground lug to the shunt and then move the 1/0 wire that was connected to the ground lug and goes to the negative of the battery to the other side of the shunt. The 2/0 wire that is connected to the negatives of the batteries you can leave as they only join the negative bus of the batteries together and are crucial to joining the 2 batteries together.
To tell if you have the shunt wired correctly you can leave the negative wire from the battery to the shunt disconnected and you shouldn't have anything in the unit be able to turn on other than what is coming from the engine battery. But you can disconnect the engine battery negative as well and then absolutely nothing should work.