Battery/Stop-Start Issue

WranglerMan

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@frajnai my JL had the main battery fail at 7 months and it’s a daily driver, factory batteries just are a crap shoot on how long they last, I had a Ford Fusion that had the battery die about 2 years in and it was garage kept, daily driver and not really exposed to any cold weather, if I were to replace the main battery it would be a beefier 700+

Im sure battery choices are lean for the JL but surely someone besides FCA has one to offer
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frajnai

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@frajnai my JL had the main battery fail at 7 months and it’s a daily driver, factory batteries just are a crap shoot on how long they last, I had a Ford Fusion that had the battery die about 2 years in and it was garage kept, daily driver and not really exposed to any cold weather, if I were to replace the main battery it would be a beefier 700+

Im sure battery choices are lean for the JL but surely someone besides FCA has one to offer

Oh yeah dont get me wrong, im not bashing the vehicle itself (yet). And even if it were an issue with a part, I dont think its a big deal if there is a straightforward replacement, then im back in business. It doesnt necessarily mean there is a design flaw just because a part fails, and I understand that.

The only thing that really concerns me is getting dicked around by the deal for a prolonged period. I have experienced this before and it is no fun.
Im holding back my verdict until Thursday when im expecting a resolution, and ill update everyone what the solution was in case anyone else is having a similar issue. More info is always better.

All that aside, I am not willing to pay for a new battery on a 2700Km vehicle. Maybe in a couple of years ill upgrade, but right now, i expect the factory battery to work or be replaced however many times is required.
PS - the tow package, which i have, i have learned comes with a 700A battery


UPDATE #1 - So after a week without my Jeep, the dealer finally said its the alternator, and they are expecting the replacement to be in tomorrow. I hope indeed that is the root cause. I will update again after a few days of driving if this fixed the issue, or if there are further issues (whatever comes first).

Question... my Jeep has the tow package, and thus comes with the "heavy duty" 240A alternator. Does anyone know if there is a way to determine just by looking which alternator is in there? I want to make sure they put the corrected "upgraded" one in as a replacement.

UPDATE #2 (tentatively resolved) - Alternator is replaced, and vehicle is working now (but im not going on any long trips just yet). So i guess thats the root cause after all. Im a little surprised that an alternator would go @ 2700KM but i guess these things happen. Hopefully thats the end of this little adventure :)

PS - Even though my issue was something else, i took others advice here and checked the seating of all the fuses and relays in the fusebox, and holy cow! I would say around 1/2 of them were seated very loosely, where they clicked in when i pushed down on it. Im surprised i didnt have issues related to this.
 
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Nblorjer

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Stop start warning light came on.at 7500 miles on a 2018 compass. After 5 hours at the dealreship they determined that the small battery was bad but the battery was backordered and had to be overnighted from interstate. After installation they said that the main battery needed replacement and that was also backordered and had to be overnighted from interstate. On the third day both batteries were installed but would not program. They call Jeep technology and we're told that the car had to be driven 100 miles to reprogram. Dealer drove the car and after 77 miles it reprogrammed. After 4 days the car was finally returned. Besides the reprogram issue it is astounding that replacement batteries are backordered.
 

Windmutt

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Hi Novanotch,
We are glad to hear you are back at the dealer and that you are in contact with our customer care teams. We would like to look into your case further to see if there is any assistance we can offer. Please send us a PM with your VIN. Also, have you had the chance to show the videos to your dealer?
Julie
Jeep Social Care Specialist
Jeep,

I have had my 2019 Jeep JL Rubicon in 5 times in the last 6 weeks for the same Battery Protection Mode issue. Twice the dealer claimed it would fix itself if I drove it more. I drove from Scottsdale to LA and it did not resolve itself. You obviously have a design flaw based on all these responses and I am sensing the dealer just hopes I go away. I addressed this issue at just over 9000 miles and have added over 1000 miles per the dealerships instructions. I want a resolution because it was not fixed as I left the dealership and I was assured it should fix itself in a couple of days.

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Windmutt

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JLU in my possession for 7 days and had same issue (yellow A with alert exclamation) when I took possession. Dealer said was just a low battery and with some minimal driving it would charge up and alert would go away. After a week of driving and 500 miles, alert was still on. Brought to service dept today and auxiliary battery failed test. Replaced with new battery and all works fine now. Hope this helps others with similar issues.
They replaced my battery after the 4th visit and it worked fine for two days until the Battery Protection Mode issue returned.
 

Capricorn

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They replaced my battery after the 4th visit and it worked fine for two days until the Battery Protection Mode issue returned.
I sometimes get that mode when I am not doing enough freeway driving. These days, happening a lot. But if I go for a spin on the freeway, the next day it disappears.
On my wife's Grand Cherokee also we used to see this happen. But on her car, we had to replace one of the batteries - happened in the second year because it wasn't going away even after extensive daytime freeway driving.
 

RubiRob

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So mine hasn't worked for the better part of this year. Ended up taking the batteries to NAPA and they said my AUX was fried, main was at 75%. So I replaced the AUX. Trickled charged both batteries overnight till full. Everything works normal now, but I have been paying attention to the voltage non stop now.

any time im driving, im at 14.1-14.5V always. Never more or less. When I stop, ESS activates and then starts trickling after it hits 12.9v. Is this normal?
 

Capricorn

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So mine hasn't worked for the better part of this year. Ended up taking the batteries to NAPA and they said my AUX was fried, main was at 75%. So I replaced the AUX. Trickled charged both batteries overnight till full. Everything works normal now, but I have been paying attention to the voltage non stop now.

any time im driving, im at 14.1-14.5V always. Never more or less. When I stop, ESS activates and then starts trickling after it hits 12.9v. Is this normal?
Normal is: When moving and pressing on the gas pedal, you should be around 12.8 - 13.1V, and when you release the pedal while in motion, it goes up to 14.1 to 14.5.
I know, it is rather unintuitive and totally opposite to what you expect to see.
And while ESS is active, yes - it drops down to around 12.8V and if your AC is on, it gradually decreases to 12.6V and then the car restarts automatically as it won''t allow the battery to go below certain voltage.
 

RubiRob

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Normal is: When moving and pressing on the gas pedal, you should be around 12.8 - 13.1V, and when you release the pedal while in motion, it goes up to 14.1 to 14.5.
I know, it is rather unintuitive and totally opposite to what you expect to see.
And while ESS is active, yes - it drops down to around 12.8V and if your AC is on, it gradually decreases to 12.6V and then the car restarts automatically as it won''t allow the battery to go below certain voltage.
no kidding. Mines at 14+ no matter where my throttle position is. Mines dropped to 11.9 so far at the most without the engine being triggered to start up again.
 

Capricorn

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no kidding. Mines at 14+ no matter where my throttle position is. Mines dropped to 11.9 so far at the most without the engine being triggered to start up again.
Hmmm..if it still in ESS active at 11.9V, that is unusual. As for the voltage reading when pedal is pressed, my understanding is that you are getting the reading from the alternator, hence it is in 12.x to 13.X V.
Since my last post and this one, I had to go for a drive, and observed that when gas pedal was pressed I was at 12.9 - 13.1V, and when released it was at 14.1V. With A/C and music on, ESS turned active on a long stop light, and my Jeep started when voltage dropped to 12.3.
 

RubiRob

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Hmmm..if it still in ESS active at 11.9V, that is unusual. As for the voltage reading when pedal is pressed, my understanding is that you are getting the reading from the alternator, hence it is in 12.x to 13.X V.
Since my last post and this one, I had to go for a drive, and observed that when gas pedal was pressed I was at 12.9 - 13.1V, and when released it was at 14.1V. With A/C and music on, ESS turned active on a long stop light, and my Jeep started when voltage dropped to 12.3.
Weird. Ya mines definitely at 14.1–14.5 no matter how hard that pedal is mashed lol.
 

KrzybonesJLU

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Just gonna drop my 2 cents on this. But I’ve only seen this “protection mode” come up when my iPhone is plugged in and it gets fully charged. And the only reason I would have it plugged up is because I’m using CarPlay. I haven’t had any issues when this comes up and personally I just take as the car is noticing a change electrically and it’s just protecting that specific battery. It goes away the following day.
 

neil

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Weird. Ya mines definitely at 14.1–14.5 no matter how hard that pedal is mashed lol.
If my alternator is always pushing 14+ and does not drop, even after 30-45m of driving, I would have my batteries checked individually.
 

WranglerMan

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My voltage pretty much stays above 14 all the time even after going to the Genesis duel battery system, after a long drive it will drop to like 13.8 but after being parked for a day or two it’s back over 14, I originally had the dealer check this with my stock batteries and they say all was good but that whole ESS battery thing buried below the fuse box just bothered me so I dropped the coin on a duel battery setup that I can get to the batteries without having to remove fender flares on going thru the top.
 
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