I've replaced a 4-way adapter on a car but no charging wire there. So I'm a little nervous about it since the wire is attached to a live battery. Anything I need to know? All I have to do is remove each wire from the old 7 way and put them in the same place on the new one (which is a Bargman and fits the trailer side).
I have a multimeter like this one
but have no idea how to use it.
I know all the wires are good on the existing connector, though, I have a tester for that that just plugs in.
So- anything I need to know?