ESS Dual Battery Management

Gee-pah

Banned
Banned
First Name
Andy
Joined
Nov 19, 2019
Messages
1,659
Reaction score
1,232
Location
SanFrancisco
Vehicle(s)
JL Wrangler
How did you make your Jumper...please give me the specs or where you got it. How do you keep the Aux Battery charged, or will it charge with the Jumper in place. I know it's somewhere in the thread but I would like to know exactly what you are using...Thanks, Larry
Larry, as it regards the how do I make the jumper portion of your question....and I think @Jebiruph Jerry would agree with this because it just is what it is..

by virtue of your 2019 ownership you neither need said jumper nor will it do you much good regarding its original intention...to get your 3.6L JL cold cranked if the ESS/Aux battery is dead.

A quick history lesson's required here. 2018 3.6L JLs that have not since been upgraded with a flash whose details I won't get into--because it doesn't apply to you, benefitted from Jerry's jumper because they would not crank if the ESS/Aux battery lacked adequate charge--even if the main battery had all the power in the world.

The upgraded 2018's (3.6L that is) and all model year (3.6L's) thereafter do not get stranded upon attempts to cold crank them if the ESS/Aux battery is dead. They automatically attempt, on second crank try, the main battery.

With factory or Jerry's original jumper in place the Aux battery is charged when the engine is cranked. I'm not a fan of using ESS with Jerry's jumper because with it in place, ESS events no longer solely tax the ESS battery as per factory design, instead tapping both batteries.

(Jerry's original jumper hard wired both batteries in parallel. By factory standards those batteries were always hardwired but for a second at cold crank and ESS events.)

It's probably me being too careful, but the whole idea of isolating the batteries during an ESS even,t so the main battery has enough power to bear the brunt of the load in cranking the engine does not happen with his jumper.

That is NOT a critique of Jerry's brilliance, just a contraindication for its use with IMHO, ESS.

~~~~~

Now, that said, and since Jerry's initial creation of that jumper, he has gone on to build upon that initial design and create ingenious mechanisms to allow the 3.6L JL to operate by factory, with just one (either) battery, or both batteries always connected (i.e. his jumper).

It's all great stuff, but bottom line, before you go rewiring, what best happens first is an assessment of your needs.

And if those needs are only "I need to know that if the ESS/Aux battery dies I can still crank the engine (on the second try,)" then you are "Dorothy and her desire to go home from Oz."

Your 2019 (assuming 3.6L) had that "power" all along. : - )
Advertisement

 

Mtrctylarry

Active Member
First Name
Larry
Joined
Apr 28, 2017
Messages
41
Reaction score
36
Location
Milford, MI
Vehicle(s)
2019 JLUR
Larry, as it regards the how do I make the jumper portion of your question....and I think @Jebiruph Jerry would agree with this because it just is what it is..

by virtue of your 2019 ownership you neither need said jumper nor will it do you much good regarding its original intention...to get your 3.6L JL cold cranked if the ESS/Aux battery is dead.

A quick history lesson's required here. 2018 3.6L JLs that have not since been upgraded with a flash whose details I won't get into--because it doesn't apply to you, benefitted from Jerry's jumper because they would not crank if the ESS/Aux battery lacked adequate charge--even if the main battery had all the power in the world.

The upgraded 2018's (3.6L that is) and all model year (3.6L's) thereafter do not get stranded upon attempts to cold crank them if the ESS/Aux battery is dead. They automatically attempt, on second crank try, the main battery.

With factory or Jerry's original jumper in place the Aux battery is charged when the engine is cranked. I'm not a fan of using ESS with Jerry's jumper because with it in place, ESS events no longer solely tax the ESS battery as per factory design, instead tapping both batteries.

(Jerry's original jumper hard wired both batteries in parallel. By factory standards those batteries were always hardwired but for a second at cold crank and ESS events.)

It's probably me being too careful, but the whole idea of isolating the batteries during an ESS even,t so the main battery has enough power to bear the brunt of the load in cranking the engine does not happen with his jumper.


That is NOT a critique of Jerry's brilliance, just a contraindication for its use with IMHO, ESS.

~~~~~

Now, that said, and since Jerry's initial creation of that jumper, he has gone on to build upon that initial design and create ingenious mechanisms to allow the 3.6L JL to operate by factory, with just one (either) battery, or both batteries always connected (i.e. his jumper).

It's all great stuff, but bottom line, before you go rewiring, what best happens first is an assessment of your needs.

And if those needs are only "I need to know that if the ESS/Aux battery dies I can still crank the engine (on the second try,)" then you are "Dorothy and her desire to go home from Oz."

Your 2019 (assuming 3.6L) had that "power" all along. : - )
Even though mine being a 3.6 w/ESS has the update in which the Jeep will start on the second try if the condition exists that the Aux Batt is drained low enough to not start on it's own.
Mine will start on the second try, but will give all sorts of warning messages on the center dash display until the Aux batt is sufficiently charged, which takes some time...I drove it one time with this condition and it did not fully charge the system after aprox. 100 miles of highway driving.

Jerry and Bill's N1 to N2 Jumper solution is in my mind the Best way to eliminate a poorly engineered factory design inherently prone to problems by using dissimilar batteries to run the ESS system which cause a myriad of concerns...especially for a person like me that drives my Jeep mostly occasionally which I always keep on a Deltran fully automatic 3 amp battery charger/maintainer when not driving for more than a few days.
Sounds like a good solid solution to run vehicle just using main batt and having the aux batt as a standby only battery. Especially for people like me who always disable the stop/start system every time I drive my Jeep.
 

Gee-pah

Banned
Banned
First Name
Andy
Joined
Nov 19, 2019
Messages
1,659
Reaction score
1,232
Location
SanFrancisco
Vehicle(s)
JL Wrangler
Even though mine being a 3.6 w/ESS has the update in which the Jeep will start on the second try if the condition exists that the Aux Batt is drained low enough to not start on it's own.
Mine will start on the second try, but will give all sorts of warning messages on the center dash display until the Aux batt is sufficiently charged, which takes some time...I drove it one time with this condition and it did not fully charge the system after aprox. 100 miles of highway driving.

Jerry and Bill's N1 to N2 Jumper solution is in my mind the Best way to eliminate a poorly engineered factory design inherently prone to problems by using dissimilar batteries to run the ESS system which cause a myriad of concerns...especially for a person like me that drives my Jeep mostly occasionally which I always keep on a Deltran fully automatic 3 amp battery charger/maintainer when not driving for more than a few days.
Sounds like a good solid solution to run vehicle just using main batt and having the aux batt as a standby only battery. Especially for people like me who always disable the stop/start system every time I drive my Jeep.
If getting rid of those idiot lights is a goal, Jerry's initial jumper solution will do that because the factory wiring's isolation of the ESS/Aux battery upon startup will be overwritten by the jumper's wiring--that keeps the batteries connect in parallel 100% of the time, such the calls to any battery are calls to both batteries. As you don't run ESS..it sounds good.

But this jumper solution by no means takes the ESS/Aux battery out of the picture. Jerry's more advanced wiring schemes though do provide the functionality to do that if desired.

Larry, not to be pedantic but these thoughts I think are apropos for Jerry's more advanced wiring schemes, not the initial and morebasic jumper one:

Jerry and Bill's N1 to N2 Jumper solution is in my mind the Best way to eliminate a poorly engineered factory design inherently prone to problems by using dissimilar batteries to run the ESS system which cause a myriad of concerns...especially for a person like me that drives my Jeep mostly occasionally which I always keep on a Deltran fully automatic 3 amp battery charger/maintainer when not driving for more than a few days.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,283
Reaction score
2,413
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
Even though mine being a 3.6 w/ESS has the update in which the Jeep will start on the second try if the condition exists that the Aux Batt is drained low enough to not start on it's own.
Mine will start on the second try, but will give all sorts of warning messages on the center dash display until the Aux batt is sufficiently charged, which takes some time...I drove it one time with this condition and it did not fully charge the system after aprox. 100 miles of highway driving.

Jerry and Bill's N1 to N2 Jumper solution is in my mind the Best way to eliminate a poorly engineered factory design inherently prone to problems by using dissimilar batteries to run the ESS system which cause a myriad of concerns...especially for a person like me that drives my Jeep mostly occasionally which I always keep on a Deltran fully automatic 3 amp battery charger/maintainer when not driving for more than a few days.
Sounds like a good solid solution to run vehicle just using main batt and having the aux batt as a standby only battery. Especially for people like me who always disable the stop/start system every time I drive my Jeep.
The worst thing FCA did on dual batteries besides location is size, this from my research is the worst possible setup having batteries of dissimilar size, there are multiple ways to correct this and it just depends on your needs and how deep you want to dig in your pocket

20F08B46-E956-441F-B284-4591B9A56556.jpeg
 

Gee-pah

Banned
Banned
First Name
Andy
Joined
Nov 19, 2019
Messages
1,659
Reaction score
1,232
Location
SanFrancisco
Vehicle(s)
JL Wrangler
The worst thing FCA did on dual batteries besides location is size, this from my research is the worst possible setup having batteries of dissimilar size, there are multiple ways to correct this and it just depends on your needs and how deep you want to dig in your pocket

20F08B46-E956-441F-B284-4591B9A56556.jpeg
Will:


I would have loved to be a fly on the way at Stellantis when this system was being designed.

As sure as I can be, without being there, at least a couple of engineers, whose knowledge of science probably far exceeded that of fashion--and the suits the executives were wearing at said meeting--pointed these things out about dissimilar batteries, while the bean counters ran the numbers of creating a design like seen in the Genesis system, over what's in place now, or even over a single battery system, and the suits decided upon what we have now.

"If it doesn't work well, the aftermarket will address it," I'll bet was said or at least thought at said meeting.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,283
Reaction score
2,413
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
Will:


I would have loved to be a fly on the way at Stellantis when this system was being designed.

As sure as I can be, without being there, at least a couple of engineers, whose knowledge of science probably far exceeded that of fashion--and the suits the executives were wearing at said meeting--pointed these things out about dissimilar batteries, while the bean counters ran the numbers of creating a design like seen in the Genesis system, over what's in place now, or even over a single battery system, and the suits decided upon what we have now.

"If it doesn't work well, the aftermarket will address it," I'll bet was said or at least thought at said meeting.
I‘m sure cost factored into the design of using the smaller ESS battery, my guess is the engineers were directed by the bean counters to tell them design a system that allows the JL to be powered during an ESS event with the most economical option they could come up with and in the end never gave much thought to ease of repair or longevity of components and just considered the batteries a disposable option.

Batteries that are available today just don’t last as long as they did years ago due to the environmental control most battery makers are made to hold standards to and couple that with the huge parasitic draw that all these newer vehicles use and then finish it off with no regular battery maintenance that most owners don’t do because most of the general public just gets in their vehicle and presses the button and goes down the road.

We all know know from Jerry’s @Jebiruph great work and time he took to give us all a very detailed working knowledge of the JL’s ESS system and then designed and shared his great way to bypass this system for a small investment with little to no impact on the system and we should all be thankful for all the time he’s invested in this and continues to give us more info as he discovers it and with this knowledge we as owners can decide what best suites our needs ranging from just moving a few cables for a $0 investment to system like Genesis or REDARC that come at a significant investment and to be truthful FCA could have easily addressed this by just having two full size batteries that were more easily accessed.

Batteries don’t last forever and we all know this but for something as consumable as they are there should have been a better design.

Is the Genesis system I have perfect ….NO ITS NOT…there are a few things that IMHO could have been addressed differently but Shane, Mike and all the rest over at Genesis Offroad designed a system that made it super simple to install for the typical person that has basic skills, and used components that are readily available to replace if and when they fail.

I won’t go into what I consider short comings as there are only a few but again this is only my opinion and when my batteries need replacing down the road I will attempt to address at least one or two but who knows I may have another Wrangler by then and maybe FCA will have a better design ( doubt it )

Anyway I say to all and always have …..If your happy with the original design using no jumpers or bypasses good for you and to others that don’t like it there are a host of other options and you as the owner have to choose what suits your need and pocket.
 

SwissSteph

Well-Known Member
First Name
Steph
Joined
Oct 29, 2019
Messages
294
Reaction score
194
Location
Switzerland
Website
www.swissjeepjl.com
Vehicle(s)
JL Wrangler Rubicon - Hella Yella - 2.2 Diesel
Vehicle Showcase
1
Hello to all,

I tried to read and follow the topic, but my English is very basic and I translate everything with "google".

I would like to permanently remove my AUX battery and use my Tazer to turn off the ESS automatically.

My question, is there a solution in this idea and is there a good tuto to do the job?

Thank you in advance for your advice and your answers
 
Advertisement

Hothead Headliners
 
Advertisement
Top