Auto STOP-START Stopped on its Own

ubbb69

Member
Eddie I am having an issue with auto start also but not sure it is related. Apparently Jeep wants the battery to stay around 12.6v to get as good of fuel mileage as possible. Only below that does it call for charge. When on
A long drive my battery constantly drains and only seems to charge while coasting. I made a video on the way to dealer then he rode around with me for about an hour with his tablet monitoring what the system was calling for and where it was at. It was all up
To
Snuff with what Jeep
Was asking of the charging system. I am not going to start a you tube account to post but I can send it to someone if they will
Post it.

I did read your posts. What was your 2016? 2018 JKs even use old tech charging along with many other vehicles.

You are right it should not drain over mileage. It should maintain the battery. Did you add accessories to the jeep or is it still stock?

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We have a 2016 2500 with Cummins and an 2016 srt charger. I have a winch on the Jeep but have it unconnected as this issue was happening and wanted to sort it out first.
 

WWRuby_Svi

New member
12.4v isn’t considered that low of a voltage. The JL was designed during the Obama era where fleet fuel mileage was a top priority. So lower charge voltages and lower amp hours in order to maximize MPG in one of the worse vehicles that FCA has seems to make sense.

I haven’t had the ESS issues yet but I have noticed various charging levels when on road trips and short drives. Yeah it’s different than I am used to but I’m not questioning the engineers on this one.


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13_gecko_rubi

New member
We have a 2016 2500 with Cummins and an 2016 srt charger. I have a winch on the Jeep but have it unconnected as this issue was happening and wanted to sort it out first.
Those are newer tech but still not newest and operate differently.

I have one other idea that could be doing it that's hard to explain so bear with me.

1) what model is the jeep?
2) do you have aux switch / hd towing?

I ask because there are 3 different batteries you can get on JL. If by chance it has the wrong battery in it could throw off the state of charge algorithms in theory. It's unlikely but there is no other reason the battery should drain faster than it maintains charge over long drives. I know people who have driven across country in theirs without issue. Beyond that i'd lean towards a sensor issue. Where did u have the winch hooked up when u had it? Battery post side if negative or the opposite side of current sensors where the stud is to hopefully keep people from putting it in the wrong side.

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ubbb69

Member
Those are newer tech but still not newest and operate differently.

I have one other idea that could be doing it that's hard to explain so bear with me.

1) what model is the jeep?
2) do you have aux switch / hd towing?

I ask because there are 3 different batteries you can get on JL. If by chance it for the wrong battery in it could throw off the state of charge algorithms in theory. It's unlikely but there is no other reason the battery should drain faster than it maintains charge over long drives. I know people who have driven across country in theirs without issue. Beyond that i'd lean towards a sensor issue. Where did u have the winch hooked up when u had it? Battery post side if negative or the opposite side of current sensors where the stud is to hopefully keep people from putting it in the wrong side.

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It is an 18 jlur with towing and switches. The winch has not been hooked up to the Jeep battery at all. I did not want any excuses when I had it looked at. I am not under the assumption that it is functioning incorrectly as we also bought a JLU sport and it operates in the same way. It also has towing and switches. Do you believe it is malfunctioning?
 

13_gecko_rubi

New member
It is an 18 jlur with towing and switches. The winch has not been hooked up to the Jeep battery at all. I did not want any excuses when I had it looked at. I am not under the assumption that it is functioning incorrectly as we also bought a JLU sport and it operates in the same way. It also has towing and switches. Do you believe it is malfunctioning?
Well you said ESS disables on long road trips and stops working? Or did I read that wrong? If I did sorry.

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13_gecko_rubi

New member
Well you said ESS disables on long road trips and stops working? Or did I read that wrong? If I did sorry.

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Nevermind i reread it and got confused since was posted in here that your ESS was shutting off. You just saw battery voltage was lower than what you expected. Ya it is totally normal. The battery is fully charged. It's not constantly being overcharged like constant alternator output vehicles. My bad. At least I provided some background how it works lol.

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ubbb69

Member
I am pretty good with most systems and understanding parameters of said systems. Back in the “shock and awe” era I worked on f16’s. Some of the newest tech I am lacking on though.
 

BillArnett

New member
...Did u add extra accessories to the vehicle? If so where did you tie them in? You didn't put anything to the negative terminal on the battery post side of the current sensors did you?

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I connected my compressors to one of the two bolts on top of the negative battery post, just like Eddie did in his winch video. Is that not correct? Where is that current sensor? Is it the black thing below those two bolts?
 

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