If I'm chasing a parasitic draw, can I automatically eliminate a power outlet/cig lighter, radio, speaker, light, etc. if it has been disconnected? Can the wiring that is hooked up to nothing still be the source of a parasitic draw?
Go on Youtube and watch Scotty’s video. Do on Youtube How to Fix Battery Drain in your own car. Scotty. That video will answer your question.
You didn't mention your year, make and model car.
Pull fuses one at a time and monitor the battery draw with a multimeter. When you've found the fuse that is causing the parasitic draw, then you find what's causing the parasitic draw with a circuit diagram showing that particular circuit, or circuits, and go from there.
Cigarette lighters, at least back in older times, were by default an open circuit unless there's something in the socket that's electrically conductive and is touching both the inside of the socket and the outer ring at the same time. Cars like my '99 Ranger that have actual cigarette lighters are always hot on the inner side, key or no key. You need to press in the cigarette lighter for the circuit to complete. The cigarette lighter automatically pops back out when the resistor inside the lighter is sufficiently hot and breaks the circuit again.
More recent cars don't have "cigarette lighters" serving their stated purpose anymore (lighting cigarettes). Newer cars for the most part operate on a timer or shut off when you open the car door and the car is off. My wife's 2017 Mustang has this feature on her former cigarette lighter.
