(Disclaimer: Theories regarding the 3.6L ESS starting process are educated guesses, here's mine.)
After months of people suggesting that the PCR separates the batteries before a cold start, I finally tested this several weeks ago. I found that the PCR is activated for a very brief instant...
I have searched the forum and haven't seen this issue, so I apologize if I missed it in my search.
I have a manual transmission and I didn't realize that I had the ESS feature until I started to get out of the Jeep this morning and it started up as I exited - I had been sitting there trying...