Can’t Identify Where Plug Goes

I purchase a used 2013 310 and the previous owner installed a black electrical box with a wire to the ground and ne to the powers on the battery. Then the last lead was plugged into the plug that powers the dash. Kind of Mickey Mouse so in trying to figure out what’s missing and where should the plug go into? I attached two photos one of the plug and one of the box yellow wire went to positive battery terminal and black to negative terminal and the red was pushed into the plug? Seams wrong to me?

I may have identified the black box it appears to be a Moto LED IC relay for DC

I figured it out it’s the relay for the turning indicators. It’s an aftermarket part for led indicators. I’m thinking I can do a cleaner install when I put it back together.