My auto stop start saga

calemasters

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In late 2020, we noticed that the auto start stop function stopped working in my wife’s 2020 JLUR. Her Jeep was just one year old. No warning notifications, we just noticed it never worked. Scrolling down the EVIC, it just said battery charging. Took it to the dealer, and they said the driver seat sensor was bad and they ordered a replacemen. That took about a month total. It worked fine for few days, then the same thing again. Back to the dealer, this time it’s the Intelligent Battery sensor. Ordered it, installed it, worked fine for a few days, then same thing. Took it to a larger dealer a little further away. They diagnosed it as a bad power control relay. Ordered it, installed it, worked a few days, then same thing. Another trip (always two trips, one for diagnosis and second for installation), this time the Z fuse. Guess what—-same result.

Each trip, I told the service adviser the info I found in this forums, namely it’s almost always the batteries and probably the aux battery. They told me that their hands were tied—- Jeep required them to follow a certain process, step by step. But, they too said it’s almost always the batteries.

Finally, on the next trip we went back to our local dealer. Took it in around 11:00 am, they called at 1:00 pm to say the batteries were bad and they replaced them. The auto start stop is back to working again. Now my wife just has to remember to turn it off each time because she hates it😆. We went to all the trouble because we were nervous that something was wrong and didn’t want her to be stranded somewhere with a dead Jeep.

Everything was fixed under warranty. But it sure cost Jeep lot of money and time to follow their corporate process, and it was incredibly inconvenient for my wife and I.

Jeep should debit the dealers for everything they did which did not fix the problem. If I was Jeep, I would only pay for the battery replacements - that's what fixed the problem.

Also, what if Jeep incested that the dealer's train the techs to fix it right the first time? What a concept. Also, I think Jeep owes you for all the BS you went through.
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Dave928

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i just got the AutoPark and ASS faults today. stopped by the dealer to make an appointment and when i told her the faults, she beat me to it... "it's probably one of the batteries, we'll check them when you bring it in".
 

Centurion07

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Does doing what you did disable the ESS feature, or just use the main battery to power it?

I have a Tazer JL Mini that I will be using to disable the ESS. If I do this is it still necessary to remove the Aux battery?
It leaves ESS fully operational, powered by the main. So, no warning lights, etc. I let my Tazer keep the ESS turned off as well.
 

Steph1

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Same story here, once I saw that the stop/start wasn't working anymore AGAIN, no matter the length of trips I took, I ended-up installing an under hood charger with an extension that runs to the front of the Jeep, like a block heated power cord does.

Within the first 12 hours, both batteries were fully charged.

Since then, I plug-in the Jeep whenever I know it wont see lots of mileage in the near future.

Going on 4 months and its worked like a champ. Not only does stop/start work immediately, but I've seen a good mpg improvement since the alternator isn't constantly charging the batteries.

Here's the thread that I started regarding this. Intersting info in there.

https://www.jlwranglerforums.com/forum/threads/ess-problems-need-input.76146/
 
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AVGeek99

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It leaves ESS fully operational, powered by the main. So, no warning lights, etc. I let my Tazer keep the ESS turned off as well.
Do you have any idea if removing the battery and powering ESS off the main batter has an impact on warranty?
 

Centurion07

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Do you have any idea if removing the battery and powering ESS off the main batter has an impact on warranty?
I have had - attempted - two warranty claims. Both got idiotic responses from the dealer/FCA. I think putting too many decals on your Jeep might affect the warranty.
 

Rhinebeck01

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Do you have any idea if removing the battery and powering ESS off the main batter has an impact on warranty?
@AVGeek99

IF you read / do forum research, you will see that no one here recommends or encourages other's here to run with just the Main and still to routinely use ESS.

Sure.... run with just the Main is aok.. I have for about 2 yrs.+, BUT .....if you run with just the Main you want to not use or minimize use of ESS.

You either push the ESS button each time you use the JL, or you use a Tazer JL or a Smart Stop Unit to do the button push for you each time you run the JL. Yes. occasional use of ESS is aok.

As for warranty.... You can run with just the Main by using an $9.00+- 40 amp fused bypass jumper along with disconnecting the Aux battery, negative cable that connects to the Main's Neg terminal...

When your JL, goes to the dealer for a Service Dept. visit, it takes about 3 min. to remove the jumper and reconnect the Aux, neg. cable before the visit.. You do not tell the dealer and they do not have a clue..

Yup, you tell them what you have been doing and sure they could use it against you so to speak..

.
 

Luxy60

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Going on 4 months and its worked like a champ. Not only does stop/start work immediately, but I've seen a good mpg improvement since the alternator isn't constantly charging the batteries.

Interesting, since the whole point of ESS is to improve save fuel and lower emissions.
 

AVGeek99

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@AVGeek99

IF you read / do forum research, you will see that no one here recommends or encourages other's here to run with just the Main and still to routinely use ESS.

Sure.... run with just the Main is aok.. I have for about 2 yrs.+, BUT .....if you run with just the Main you want to not use or minimize use of ESS.

You either push the ESS button each time you use the JL, or you use a Tazer JL or a Smart Stop Unit to do the button push for you each time you run the JL. Yes. occasional use of ESS is aok.

As for warranty.... You can run with just the Main by using an $9.00+- 40 amp fused bypass jumper along with disconnecting the Aux battery, negative cable that connects to the Main's Neg terminal...

When your JL, goes to the dealer for a Service Dept. visit, it takes about 3 min. to remove the jumper and reconnect the Aux, neg. cable before the visit.. You do not tell the dealer and they do not have a clue..

Yup, you tell them what you have been doing and sure they could use it against you so to speak..

.
Yes I have a Tazer JL Mini and plan to have ESS disabled, or more specifically have the Tazer remember my last ESS config, set to off. Is having ESS permanently disabled by the Tazer enough to avoid the problems described in this chain, or is further action as you or @Centurion07 have described also necessary?

Do you know of any YouTube videos that show how to do this?
 

jeepoch

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All,

For an interesting little tidbit of trivia related to the theme of this thread, I was one of the Powertrain Software Engineers at Chrysler who first implemented the 'Tell-Tale' feature. Essentially this was the beginning of a full blown on-board, black-box, flight-recorder within the Engine Controller.

This feature was implemented initially to just save on exorbitant warranty costs. At the time (late 1990's for the 2002MY vehicles and beyond), the 'Tell-Tale' functionality was conceived to basically keep dealerships honest. Before then, most dealership technicians would simply 'dive-bomb' instead of troubleshooting. They would just replace every possible component relating to whatever issue was reported.

This lead to very (very) expensive warranty claims. So Tell-Tale was then used to validate the captured Diagnostic Trouble Codes (DTC's) to the various things that the dealership actually replaced. Corporate would then reimburse for only the component(s) as detected from the codes. The dealership would then have to eat the cost for replacing everything else.

Dive-Bombing troubleshooting practices practically disappeared overnight. Many dealerships likely faced real financial hardships those first several years until they properly trained their tech staff to diagnose every issue properly. Of course this then meant following the corporate published servicing procedures more closely. 'By-the-book' as the old cliche goes.

It sounds like the pendulum has now swung too far in the other direction. Dealerships now have almost zero latitude in troubleshooting problems outside of the corporate service troubleshooting flowcharts.

So I suppose you can partially blame me for any unintended consequences.

I too have a 2019 Sport S 3.6L Auto with the God-Awful AUX battery implementation. My ESS routinely disables itself due to 'Battery Charging' conditions. However, using a battery tender at least once a week appears to keep the ESS system pretty happy. Whoever thought that a mini AUX motorcycle battery connected in pseudo-parallel with the full sized MAIN was a good idea, should have been shot, fired and then shot again.

Yet I'm one of the oddballs that actually doesn't mind not burning fuel when idling (except off-road). It blows me away that so many people go through so much time, money and effort in preventing the need to press that simple little pushbutton on the dash. If enough consumers continue to bypass the federal environmental EPA mandates, the current batch of Powertrain Engineers may be tasked to implement a much more bulletproof, permanently enabled ESS mechanism.

However, based on our current climate (pun intended), resistance may not only be futile but rather totally irrelevant. Our freedoms are being not-so-slowly eroded (everywhere). The happiness of a constantly running internal combustion engine will most likely also be nothing more than a distant memory.

Sorry, but I truly wish I could have a more optimistic outlook. Please don't condemn me for observing that fact.

Jay
 
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RoadiJeff

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Do you have any idea if removing the battery and powering ESS off the main batter has an impact on warranty?
You better believe it would if they found out and you brought it in for any type of electrical warranty claim. We're not talking about changing the color of floor mats, that's a big electrical modification from how it was originally designed to work. They will look for any reason to deny a warranty claim and that would be a good excuse. See the post right above mine for more details.
 

Steph1

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Going on 4 months and its worked like a champ. Not only does stop/start work immediately, but I've seen a good mpg improvement since the alternator isn't constantly charging the batteries.

Interesting, since the whole point of ESS is to improve save fuel and lower emissions.
Yes totally, but having the batteries fully charged all the time makes an even greater impact, since when you leave home, the ESS doesn't need a while to charge before actually working on that ride. As soon as the engine reaches normal operating temp. the ESS works immediately.

Best example is me admitting that I haven't plugged it in much lately because I use the Jeep on a daily basis. Well, since it takes longer for the ESS battery to charge, meaning that the alternator has to charge it before it reaches enough power to operate, I have seen my MPG go down by 2L/100kms (almost 2.5mpg). Still 2mpg better than before, but not as good as when I keep it fully charged all the time.
 

jeepoch

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@RoadiJeff,

Another not so small detail to your post. At the time of the Tell-Tale's implementation, the idea was to only capture DTC codes. This information would only last until the memory space was filled and new data would then roll over the older at the top of memory. Essentially, just long enough for the last servicing event to be analyzed. Approximately somewhere between several days to a month depending essentially on the number and frequency of DTC codes thrown.

However, that was two decades ago. I have since moved away from that rat race they call the automotive industry. By now, the Tell-Tale feature could have morphed into a completely different animal. It may now be a comprehensive flight recorder that captures many more data points, such as real-time telemetry data. Things like speed, throttle position, steering angle, braking pressure, etc. In other words, just about everything. Even with newer generations of electronics, the time of data retention could now potentially be a lot longer than weeks.

I don't know this for certain, since I'm no longer involved, but that would be the natural progression of this feature set. Of course there would then be legal issues outside of just warranty analysis. Questions regarding who could get access to this information would then become important. Having court orders to gather this type of info for insurance or liability determination for accident investigations would then not be out of the realm of possibility.

So today's vehicles may be able to gather more information than you realize. If removing the AUX battery and rewiring it to work subsequently throws any codes whatsoever, (independent of turning on the Malfunction Indicator Light (MIL) or Check Engine indicator), even during the modification sequence itself, corporate would certainly know it.

They'll know about everything including using third-party products such as Tazers and the like. Codes are thrown anytime when removing the Security Gateway module (SGW). However, corporate may be somewhat tolerant of this since so much potential revenue may be generated from after market modifications. Still, they'd know.

You are certainly playing with fire (warranty wise) by rewiring or fiddling with anything that can be electronically captured by 'Tell-Tale'.

Again, this is just conjecture on my part but an educated one. Just food for thought if you value your warranty, or purchased any type of extension.

For reference, I own a Tazer to adjust my increased 35" tire size. Even though my lift is Mopar (dealership installed). So I too am rolling the dice a little bit. But I'm living with and tolerating this piss-poor ESS design because I love the rest of my JL Wrangler so much more. The weekly battery tender charging cycle is nearly no trouble at all.

Jay
 
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AVGeek99

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So going the route of simply using the Tazer to "remember" that I had disabled ESS the last time the vehicle was running. Will that prevent the issues with the Aux battery described in this chain?
 

jeepoch

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So going the route of simply using the Tazer to "remember" that I had disabled ESS the last time the vehicle was running. Will that prevent the issues with the Aux battery described in this chain?
Chris,

No. If you don't have an eTorque power plant you have the mini AUX battery. The problem is the charging of two dissimilar sized batteries in parallel. The propensity of this configuration is to cause the smaller battery to under charge over time because the main absorbs most of the energy. As the AUX gets weaker it then charges off the main when the engine is off thus further draining the main. Upon the next ignition on event, the alternator is forced to over work at higher voltage levels in order to recharge everything back to where it was.

Obviously this will only get worse as the batteries get weaker over time. Even worse yet, the lowest capacity battery, the mini AUX is exclusively used to control the starter relay. If its charge gets too low, the vehicle is rendered dead. Thankfully the 2019MY year and later models now have a mechanism to reconnect the two batteries in parallel so that the main can then contribute to starting the engine on the second crank attempt. There's a TSB to fix the 2018's but I don't have that information at the top of my head. The details of which are certainly elsewhere in this forum.

So no, simply disabling the ESS will not fix this piss poor design.

It sounds like this implementation was ram-rodded together at the last minute in order to meet the latest EPA regulations for either carbon tax credit or CAFE standards. No Powertrain Engineer in their professional capacity would ever have designed this crap intentionally. I'm certain this was not their intention and decisions above their pay grade brought this all about.

My guess is that the mild hybrid eTorque system was implemented for no other purpose than rectify this AUX horseshit. Everything in the sales brochure is to deflect and sugar coat it's true purpose.

Jay
 
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