Here's my attempt at a diagram that illustrates the battery connections for the 3.6L ESS dual batteries. Hopefully this will help make sense of why things work the way they do. I tried to show that when you pull the battery terminals off of the battery, there is still an electrical connection between the cables attached to the battery terminal. Let me know if you see anything needing correction.
Version 2.1 (updated 11/16/18)
Here's an update to the original drawing. All the electrical connections are the same, but I've added a little more detail and some explanations with my understanding of why and how some things are behaving the way they do.
Physical Appearance Version (updated 08/02/19) (added PDF 10/13/19 - jumper diagram 2 )
This new version is based on the physical appearance and location of the components.
Additional 3.6L ESS system information is available here.
3.6L ESS Dual Battery Consolidated Information
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