Most power cables like that will have a raised ridge or a line (solid or dashed) on the ground line.
I know it was stupid but it was a time of desperation.. On my first setup I needed my truck hitch ASAP so I had to just snip wires.. That included the power wire to my backup camera..
Now, I want to install it in my new truck but have no idea which is the power line and which is the ground.. Anyone have any ideas of how I can figure it out? I know if I do it wrong the first time most likely it will be fried!
As above, look for the raised ridge, or white strip and match it to the off cut.