3.6L ESS Battery Diagram

Jebiruph

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36L dual batteries.PNG


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)
36L dual batteries 2.1.PNG


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 )
underhood jumper 3a.PNG


This new version is based on the physical appearance and location of the components.


(updated 04/13/2019)
Additional 3.6L ESS system information is available here.
3.6L ESS Dual Battery Consolidated Information
https://www.jlwranglerforums.com/forum/threads/3-6l-ess-dual-battery-consolidated-information.2




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Jeepsk8

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So the aux batt doesn't go to the starter? I'm still trying to figure out why it's there.
 
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Jebiruph

Jebiruph

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So the aux batt doesn't go to the starter? I'm still trying to figure out why it's there.
My current understanding is that the batteries are connected together (through the PCR) until auto stop kicks in, then they are disconnected and the aux battery runs the accessories so the main (cranking) battery can maintain it's charge for restarting. I tried connecting a couple volt meters to monitor when the batteries are connected and when they are not, but the ESS would not operate with the volt meters connected.
 

porcusRex

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i wonder if you can (i suspect you can but it might be complicated) simply remove the aux battery from the system, reroute the wiring and program the system so that ESS is never enabled.

Something to think about... this setup doubles the number of points of failure and adds complication simply to address EPA issues.

Another thing that might be coming up. the BSG. if you look at that setup on the RAM it looks sorta like a small mailbox setting on the front of the engine, then you add the 48v battery with all the heating and cooling. more added complexity for the same reason, to address EPA issues.

I owned a CJ5 back in the day. not a perfect vehicle but it was relatively simple, with fewer things to break. as someone who would occasionally go somewhere way off the beaten track, the less things to fail the better. the complexity of the current wrangler and the addition of more complexity isnt something i want. if i wanted a hybrid system, i would buy a prius. i have respect for that car too and considered buying one. for its intended purpose, high mpg in a urban/suburban environment where breakdowns result in a relatively easy tow. having a jeep break down 50 miles into the back of beyond is not something i wanna contemplate.
 

OldGuyNewJeep

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Thanks. I did a search. I guess I didn't word my search in a way to come up with viable results.
Built in search feature is awful. To do a proper search use the site: keyword in google. For example:

site:jlwranglerforums.com kill 12v
 

intheaspens

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I love this. So the poor engineers at FCA have to develop this Rube Goldberg with two batteries (no environmental impact in lead acid batteries!) to satisfy an EPA diktat to save a thimbleful of gas emissions and put extra load on the starter system so we can use more batteries.

Great job, EPA! :cwl:
 

[o!!!!!!!o]

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I love this. So the poor engineers at FCA have to develop this Rube Goldberg with two batteries (no environmental impact in lead acid batteries!) to satisfy an EPA diktat to save a thimbleful of gas emissions and put extra load on the starter system so we can use more batteries.

Great job, EPA! :cwl:
Right! Someone pointed to what should be the patently glaring hypocrisy, ...
 

Rhinebeck01

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5/2/19 ....... I quit JLWranglerForums!
Temerity if I’ve ever seen it, ... Of course he gets paid. The people benefiting the courtesy of the thoughtful advice aren’t paying him or them. More information, particularly free, more power to all. Yeah, so, funny, if you’re you and not someone looking for exactly what’s been kindly offered. We have people respectfully, gracefully, seeking this advice. So, I don’t see the humor or your sarcasm as useful for comment or for those kindly seeking this advice.
I can't understand what the heck you are trying to spew out in the quote above. :cwl:
 

Medictrode

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Thanks for doing this... This was one thing on my list of chores to do. I wish to understand this pointless system do I can bypass it as the vehicle ages and I go out of Warranty. The whole ESS system has trouble written all over it for sure. Such a shame that we need to deal with such a thing on an offroad mostly gearhead vehicle.

I suspect that with a few jumpers this separate battery can be removed after you Tazer the ESS. If anyone attempts this and realizes that there is a sensor blocking your efforts share it here. I am good at fabricating circuitry to bypass such things.
 

Medictrode

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On second thought..... It would be kinda silly to completely remove a perfectly good battery that could be used for emergency starting if the main battery ever goes flat... I watched the Videos with the wiring Diagrams and it looks fairly simple to disable the aux battery system in general... If I do figure it out it would be cool to hook up a battery isolator to the second battery so it can stay charged.. Then keep the grounds intact and add a solenoid on the positive side with a momentary push button switch somewhere in the cab, and boom you have a emergency battery booster built in... This is just all theory however, I haven't actually gotten my hands on anything so if you decide to do such things proceed with caution...
 

                           
























































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