Stop/Start Not Ready-Battery Charging

WranglerMan

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I occasionally put my Jeep on a tender. The Start/Stop may work for a day or two. Then it dies again.

I have had the AUX battery replaced once. I will have the dealer look at it again when I take it in for its annual check up.

I write this off to a bad design that is prone to fail. Please change my mind!
I wish I could convince you it’s a great design but FCA dropped the ball on this design using it on a Jeep Wrangler.

If your Jeep sits a lot it’s best to put it on a tender/maintainer that is sized correctly for the stock batteries so like a 5 amp NOCO but in all honesty I believe you could use a 10 amp NOCO as when the Jeep is idle the batteries are connected as one so it’s just one big battery but that smaller motorcycle ESS battery is just sad as it’s not sized the same in amp hours as the 70 aH full size battery plus I honestly don’t believe the batteries that are used are of acceptable quality.

There are ways around bypassing the baby battery and just maintaining it for backup purposes but as we all know batteries start to degrade from day one and regardless of what batteries are used they all have a life cycle but some have shorter lives than others based on their design and quality of construction.

You as a Jeep owner have to decide what your needs are and go from there but the choices are pretty simple

1. Maintain the original design and just be diligent on maintaining the factory batteries

2. Bypass the aux battery and DON‘T USE ESS but still maintain them.

3. Go to some type of better dual battery system ( There are a few choices )

Regardless of what battery system you go with if your Jeep is not driven a lot use a quality maintainer to keep the batteries at peak so you get the maximum life from them.
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willcasp

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I wish I could convince you it’s a great design but FCA dropped the ball on this design using it on a Jeep Wrangler.

If your Jeep sits a lot it’s best to put it on a tender/maintainer that is sized correctly for the stock batteries so like a 5 amp NOCO but in all honesty I believe you could use a 10 amp NOCO as when the Jeep is idle the batteries are connected as one so it’s just one big battery but that smaller motorcycle ESS battery is just sad as it’s not sized the same in amp hours as the 700 aH full size battery plus I honestly don’t believe the batteries that are used are of acceptable quality.

There are ways around bypassing the baby battery and just maintaining it for backup purposes but as we all know batteries start to degrade from day one and regardless of what batteries are used they all have a life cycle but some have shorter lives than others based on their design and quality of construction.

You as a Jeep owner have to decide what your needs are and go from there but the choices are pretty simple

1. Maintain the original design and just be diligent on maintaining the factory batteries

2. Bypass the aux battery and DON‘T USE ESS but still maintain them.

3. Go to some type of better dual battery system ( There are a few choices )

Regardless of what battery system you go with if your Jeep is not driven a lot use a quality maintainer to keep the batteries at peak so you get the maximum life from them.
You are correct. You won't convince me. The system fails my basic use case. On average, I drive my jeep 4 times a week. 20 miles on days I drive it. I should not need to do anything to make the system work. It should just work.

As an example, I have an Audi Q5 that can sit for a week. ESS will work just fine.

Since FCA uses ESS to meet their MPG statements with the EPA, the system needs to "just work" for standard use cases. As you can see in the threads, it clearly does not. This seems fraudulent on the part of FCA to me.
 

WranglerMan

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You are correct. You won't convince me. The system fails my basic use case. On average, I drive my jeep 4 times a week. 20 miles on days I drive it. I should not need to do anything to make the system work. It should just work.

As an example, I have an Audi Q5 that can sit for a week. ESS will work just fine.

Since FCA uses ESS to meet their MPG statements with the EPA, the system needs to "just work" for standard use cases. As you can see in the threads, it clearly does not. This seems fraudulent on the part of FCA to me.
The miles you drive are likely not near enough to keep the batteries especially the smaller aux charged properly, the factory batteries themselves I doubt are of good quality and when to add in the fact in your case it sits parked a lot causes sulration of the both due to their low state of charge shortens their life so it’s best to first get a good properly sized charger and keep you Jeep on it.

i personally would bypass the aux battery and not use ESS by bypassing it by whatever means you choose, there are several that have successfully bypassed it with fused jumpers and even some have used jumpers with voltage indicators and then go on a diet of regular charging keeping the aux as a sort of spare that can be used as a jumpstart, there are also several that have removed and bypassed the aux by moving the positive ESS cable to the main crank battery and disconnected the ESS negative cable from the main with success then there are some like me that removed the ESS battery and went to a system that still uses two batteries but the batteries are easier to get to for upkeep, are sized properly and are identical so they can be maintained at the same rate plus I have the added benefit of the extra power from a full sized spare that gives me power to run aux equipment longer without the worry of being stranded.

What ever route you choose batteries still need to be maintained but there are a lot better options on batteries than what the factory installed and with some tweaking on the original design with better batteries your Jeep should serve you well.

But in the end there are several options you have to address the poor design that FCA has presented us and they vary from a simple $10 fused jumper to a Genesis or Redarc battery management system that cost more than what a lot would choose to pay but this is where you as an owner has to choose what suits your needs.

I personally went to a pricier better designed dual system after carrying a jumper for backup, i never had issues where I was stranded with the stock setup but I got to the point where I wanted the additional power to run not only additional aux equipment but also have the extra boost if my main battery failed.

The system I chose still requires upkeep on batteries so no magic beans but they are better quality batteries that are sized for my needs.
 
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willcasp

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The miles you drive are likely not near enough to keep the batteries especially the smaller aux charged properly, the factory batteries themselves I doubt are of good quality and when to add in the fact in your case it sits parked a lot causes sulration of the both due to their low state of charge shortens their life so it’s best to first get a good properly sized charger and keep you Jeep on it.

i personally would bypass the aux battery and not use ESS by bypassing it by whatever means you choose, there are several that have successfully bypassed it with fused jumpers and even some have used jumpers with voltage indicators and then go on a diet of regular charging keeping the aux as a sort of spare that can be used as a jumpstart, there are also several that have removed and bypassed the aux by moving the positive ESS cable to the main crank battery and disconnected the ESS negative cable from the main with success then there are some like me that removed the ESS battery and went to a system that still uses two batteries but the batteries are easier to get to for upkeep, are sized properly and are identical so they can be maintained at the same rate plus I have the added benefit of the extra power from a full sized spare that gives me power to run aux equipment longer without the worry of being stranded.

What ever route you choose batteries still need to be maintained but there are a lot better options on batteries than what the factory installed and with some tweaking on the original design with better batteries your Jeep should serve you well.

But in the end there are several options you have to address the poor design that FCA has presented us and they vary from a simple $10 fused jumper to a Genesis or Redarc battery management system that cost more than what a lot would choose to pay but this is where you as an owner has to choose what suits your needs.

I personally went to a pricier better designed dual system after carrying a jumper for backup, i never had issues where I was stranded with the stock setup but I got to the point where I wanted the additional power to run not only additional aux equipment but also have the extra boost if my main battery failed.

The system I chose still requires upkeep on batteries so no magic beans but they are better quality batteries that are sized for my needs.
Which design did you go with? Is there a link? Did you build it up yourself?
The cars that I do not use for more than a week are kept on a tender. That helps make sure that they start when I want to use them.

I understand your points on battery maintenance, and practice them as well.
However, I will not excuse FCA of their piss poor design here. Especially considering that these designs operating as expected are essential for the MPG ratings that the manufacturer files with the government. This ends up being a failure in performance. A performance that we paid for.
Other manufacturers make systems that work given the exact same use cases. This is not some bizarre new technology. This is well proven out engineering.
FCA should not be excused for such a piss poor design.

I am more surprised that some enterprising attorney has not seen this as a multi-million dollar revenue source in a class action lawsuit. This one is fairly low hanging fruit.
 

WranglerMan

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@willcasp i went with the Genesis system and chose two Full River 750 batteries, this system suits my power needs and so far has bailed me out of a no start situation once and it was my fault but glad it was there.

You can read about it here https://www.genesisoffroad.com/ It’s not as cost effective as a simple fused jumper but you basically remove the ESS battery and original battery tray and battery then and connect everything back with new batteries ( Factory ones can’t be used )and Shane and his group with Genesis Offroad make the kit pretty simple but I was not comfortable pulling the PDC to get to the ESS battery out but you have to remove it to get the tray out so I had my favorite offroad shop here in Houston do the work for me and also had some other things done.

The system consists of a new battery tray and then two group 25 batteries that you choose and then a completed top tray that is preassembled that goes on top and it consists of a Cole Hersery smart relay and heavy duty solenoid and boost button, I won’t bore you with how it all works but Mike at Genesis and I have exchanged lots of info on design and correct operation as I had some initial concerns on the power draw of the solenoid and relay.

Heres my setup and it’s been working 100% with zero issues and the JL smart charging system is working as designed, I was doing weekly charges as I had concerns on the batteries being pulled down but now I only charge/recondition bi-weekly or if it’s going to be parked for 4-5 days and my voltage metered directly at the batteries with them isolated has never been less then 12.6 but be advised that with this system ESS becomes somewhat inoperable after (6) consecutive cycles and won’t reset until you cycle the ignition, this is the fault of the JL programming because if it sees the same voltage (6) times in a row during ESS events it assumes there’s a problem so it disables ESS but I dislike ESS and run a SSS mod to disable it so I never see this error but have tested it several times

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All this talk about having to take your jeep out for a long drive is pushing me even close to the diesel. I drive a lot of short trips and I would rather have to burn off the DPF every couple of weeks than be suddenly stranded by that stupid aux battery.
 

WranglerMan

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All this talk about having to take your jeep out for a long drive is pushing me even close to the diesel. I drive a lot of short trips and I would rather have to burn off the DPF every couple of weeks than be suddenly stranded by that stupid aux battery.
Aux will not leave you stranded, you have lots of choices..from a $10 bypass to a $1200 dual upgrade that removes that baby ESS battery, just depends on what your needs are.
 

DaltonGang

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Three days left on my warranty, and I took the Jeep in, for the ESS not working, and other issues. The IBS sensor was replaced, last year, now they replaced the tiny battery.
 

smithrd65

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I know first hand your battery is bad. I had the same issue replaced both batteries under warranty.
 

BobW

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My Start/Stop stopped working, same symptom "not ready...battery charging".
Dealer repaired, replaced voltage sensor, now working normally.
Still under warranty, no cost. (Service rep said normal cost ~ $450....).
 

Marlon_JB2

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I'm currently having this same issue. I took it in on Thursday and got a callback on Friday saying that it was fixed. They replaced the main battery. I'm thinking yay, everything's going to be ok, right?

Before I even made it home, LITERALLY RIGHT DOWN THE STREET, I noticed that it STILL wasn't working. I drove down to work later to build more Jeeps, and still, nothing. I e-mailed the service advisor a picture of my instrument cluster. Stop/Start Battery Charging. This guy assumes that they gave me a loaner with an issue. Drove home, SAME deal.

I can't wait for his reply. I'm not taking it back to them and they better not send me that survey. Zero Stars. Very ghetto. They were more concerned whether or not I bought it from them from Day 1 when I made the appointment.

They didn't even drive it. :( The odometer showed the exact same miles as when I dropped it off. So exactly HOW did they figure out that it was fixed?

TERRIBLE customer service.
 
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jeepoch

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I've written quite a few posts regarding this very crappy ESS implementation on the non-eTorque JL's. However, I've resigned myself to the fact that this system is going to always fail, whether under warranty or not. This dissimilar sized battery design is never going to work reliably, especially as the batteries get older and weaker.

If it wasn't for the fact I really like my 2019, 2 door Sport S so much otherwise, this ESS nonsense would be enough to dump it altogether. The FCA engineers should be totally embarrassed and have their motorhead credentials perminently revoked.

So I am grudgingly burdened with externally charging these batteries with a battery maintainer at least once or twice a weak in order to prevent the "ESS System Disabled - Battery Charging" condition.

Sadly it's another Jeep Thing.

Jay
 

TeleJeep

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After owning my JlU 2018 Sahara 6-sp for 3 years and 30k miles, since it’s not my daily-driver, I now keep it on a battery maintainer. The stop-start is always ready after the engine warms up.
 

BobW

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Well, when I wrote on Oct4 that "not ready...battery charging" problem was solved.... that lasted one day. After some fumbling, dealer put a different tech on my jeep. He determined that PRIMARY battery was bad and replaced it. Problem solved...this time it stayed solved (for weeks at least...).

The jeep is only for fun, driven maybe once a week, even if just to exercise it.
 

Tommywear

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It's been said already many times. At best, all I can do is restate it in other terms:

I am of the opinion that the ESS system found in the 3.6L Wrangler, with its dissimilar sized batteries, particular where one battery is so small, is mis-engineered such that it barely works consistently for the standard use case vehicle operator, let alone those who drive less frequently, shorter distances, in colder weather, and don't swap out, particularly the Aux battery, with frequencies far more repetitive than the maintenance schedule suggests.

Regularly hooking your main battery up to a trickle charger designed to not overcharge, assuming you have shore power available, or throwing say a 100 watt solar panel on a roof rack to effect same, either of which will charge both batteries while the rig's at rest, is pretty much a necessary condition to keep factory ESS running. And, of course, it is not lost on this poster that spending on household energy to economize on rig energy expenditures is worse than a zero sum gain proposition as Newton teaches us that transferred or converted energy looses some of its oomph (a "technical term") doing so.

The really short version: "It's not you, its them (Stellantis.)"
 
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