Trying to figure out if there is a negative connection somewhere on the fuse box. My understanding is that most if not all car fuse boxes have only a positive in with the negative being grounded to the chassis but I wanted to confirm. Working on my solar augment for running some of the 12v systems to save gas and generally amuse myself.
Generally you'll just put a ring terminal on your ground wire and take it to a metal bolt into the metal body somewhere. For the best in grounding, take it to one of the actual ground points used by the car's own wiring harnesses, recognizable by the usually several white/blackstripe wires attached under a bolt with rolled threads designed for best electrical contact. There are a bunch of these points all over the car, and the wiring diagram shows where (often under some trim). -Chap
Is there a connection from the fuse box to one of those points that I can Intercept for use with a battery indicator shunt and a step down converter? I'm trying to power all the 12v stuff with a solar battery bank and there are several methods I am trying out. One method involves interrupting the fuse connections on several power hungry systems and adding a second input with a switch on the first.
Not "a connection from the fuse box", no. Spend some time with the wiring diagram; it'll answer the questions you haven't asked yet, and give you better insight into the ones you have. -Chap