Stop start in battery protection mode

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,284
Reaction score
2,415
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
No warning messages. ESS doesn't engage after about 8 months of vehicle ownership. I'm a light driver, but not so light that I feel it should affect ESS. I've never had battery issues with my other vehicles. I have a 24 x 7 dash cam that when in parking mode, but it would turn off if battery voltage drops below a 12V + threshold.

I checked fuses: fine, installed and energized a trickle charger, problem went away. Still have service call this week because maybe something's defective. I'd be upset to know that to save energy (read fuel) using ESS I have to expend energy (read: electric) to charge the rig on a regular basis. That seems self defeating to me.

Then again....problem may be something else that trickle charger is able to overcome the threshold of, that wouldn't be needed once repaired.

We'll see. Will report back.
Have you taken a meter and checked both batteries for correct voltage, this is the only way to check the voltage as from what I have been told what is displayed in the EVIC is what the alternator is doing, for example my EVIC voltage display this morning was 13.5 but then I checked the battery directly and it read 12.6 but after running a few errands the EVIC displayed voltage dropped to 12.9 at idle and the battery checked again but read 12.72 so my assumption is that the alterantor only charges when needed and it does it during deceleration whether by braking or just letting off the pedal.

Again I was told by a service tech that the battery voltage displayed will swing from 12.8-14.2 depending on what the needs of the battery are and it charges it to just the 12.7 then the alternator charging drops off and does what it needs to do by monitoring the voltage thru the IBS

I am pretty old school and am used to seeing the voltage displayed steady at 14+ but was told the JL is no supposed to do that, I know several on here say there’s runs a solid 14+ all the time and have no issues and no messages displayed and ESS works fine but when mine showed a steady 14 volts the message displayed in menu #6 on the EVIC said “start/Stop not ready battery charging” but it never had any issues starting and running but the dealer ran a test and advised the main battery was bad and once they replaced it all went back to working correctly and the voltage displayed again runs 12.7-14+ but once I have been driving for awhile it slowly drops down to the 12.8 range and only ramps up when I decelerate
Advertisement

 
Last edited:
OP
OP
Jeepney18

Jeepney18

Well-Known Member
Joined
Aug 9, 2018
Messages
417
Reaction score
410
Location
Bay Area, California
Vehicle(s)
2008 Toyota Corolla S, 2018 JL Sport S Unlimited
Vehicle Showcase
1
Did you ever get this resolved?

Mine had the same message and it was in the shop for 17 days until FCA engineers had them do a re-learn procedure on the Jeep. Now all is well.
After @Joltes posted this page of the manual, I understood that it was supposed to do that.
batt.jpg
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,284
Reaction score
2,415
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
This evening I tested ESS a few different ways and after it reported it was ready and I had been driving about an hour coming home my voltage at idle was in the 12.6-12.8 range and was pretty much the same rolling down the road and as I slowed down either by letting off the gas or braking the voltage would ramp up to over 14 and and once idle again with ESS not engaged voltage would drop back down and I was told this is normal behavior and it’s controlled by the IBS and tells the alternator when to charge and from my understanding it charges when not under a load for the mileage benefit and also it’s supposed to only maintain the minimal voltage on the battery and supposedly this helps battery life by not constantly overcharging it.

The above was told to me by one service tech and also a service advisor, I truly would like to know if this is true or something they made up but honestly it makes sense and my JL Sahara had done this from day one of ownership but then after putting in my programmer the voltage slowly crept up,to,over 14 and stayed there and once I removed the programmer ESS reported it was not ready as the battery was charging but I never received a battery protection mode message.

The dealer after testing advised the main battery was bad and replaced it and upon getting home I put my trickle charger on it and here we are three weeks later and my voltage after my JL has been running about an hour shows 12.6-12.8 at idle and ESS works perfectly and after it’s been sitting for a day or two on startup it usually is in the 13.5 range but drops down after about an hour of driving and again no issues

I have checked voltages at the main battery and also at N1and N2 and all three points show pretty constistant voltages and they are in the 12.6-12.8 range, again what I was told was the voltage you see displayed is the alternator output and if it’s running high your battery is low and mine was partially bad and never would fully charge so ESS never saw the correct voltage to work and that’s why it was 14+ but now it seems to only change what’s needed

I have checked ESS operation multiple times and it works perfectly as in normal stops and when things like AC or heat come on it restarts and after 5 mins and exactly 5 mins ESS automatically disengages and the engine restarts and all of this is supposed to be normal so I’m not sure who’s right as lots of you advise your voltage stays at 14+ and others say there’s floats like mine so I am hoping maybe somone has contact with an FCA engineer or tech to get the real truth but so far mine is working like it’s supposed and I have no flaked out issues like screens rebooting it error messages
 

TheWingman

Well-Known Member
Joined
May 2, 2018
Messages
193
Reaction score
162
Location
Texas
Vehicle(s)
2018 Firecracker Red JLUR
This evening I tested ESS a few different ways and after it reported it was ready and I had been driving about an hour coming home my voltage at idle was in the 12.6-12.8 range and was pretty much the same rolling down the road and as I slowed down either by letting off the gas or braking the voltage would ramp up to over 14 and and once idle again with ESS not engaged voltage would drop back down and I was told this is normal behavior and it’s controlled by the IBS and tells the alternator when to charge and from my understanding it charges when not under a load for the mileage benefit and also it’s supposed to only maintain the minimal voltage on the battery and supposedly this helps battery life by not constantly overcharging it.

The above was told to me by one service tech and also a service advisor, I truly would like to know if this is true or something they made up but honestly it makes sense and my JL Sahara had done this from day one of ownership but then after putting in my programmer the voltage slowly crept up,to,over 14 and stayed there and once I removed the programmer ESS reported it was not ready as the battery was charging but I never received a battery protection mode message.

The dealer after testing advised the main battery was bad and replaced it and upon getting home I put my trickle charger on it and here we are three weeks later and my voltage after my JL has been running about an hour shows 12.6-12.8 at idle and ESS works perfectly and after it’s been sitting for a day or two on startup it usually is in the 13.5 range but drops down after about an hour of driving and again no issues

I have checked voltages at the main battery and also at N1and N2 and all three points show pretty constistant voltages and they are in the 12.6-12.8 range, again what I was told was the voltage you see displayed is the alternator output and if it’s running high your battery is low and mine was partially bad and never would fully charge so ESS never saw the correct voltage to work and that’s why it was 14+ but now it seems to only change what’s needed

I have checked ESS operation multiple times and it works perfectly as in normal stops and when things like AC or heat come on it restarts and after 5 mins and exactly 5 mins ESS automatically disengages and the engine restarts and all of this is supposed to be normal so I’m not sure who’s right as lots of you advise your voltage stays at 14+ and others say there’s floats like mine so I am hoping maybe somone has contact with an FCA engineer or tech to get the real truth but so far mine is working like it’s supposed and I have no flaked out issues like screens rebooting it error messages
Mine was just in the dealer for this exact issue. Both batteries had to be replaced. They said the aux battery was bad and it pulled the larger battery down with it over a period of time. Now working perfectly.
 

frajnai

Active Member
First Name
Frank
Joined
Nov 29, 2018
Messages
35
Reaction score
63
Location
Canada
Vehicle(s)
2018 Wrangler JL Sport S, 2011 Mustang GT
20181013_165116.jpg
What is this battery protection mode? Stop start isn't working anymore.
So, im hearing all these electrical gremlins, thinking ah well its just the internet. I mean i feel for all those people certainly, but i figure law of averages there will be a certain amount of issues and you are likely to hear about it on the internet.
Tonight i became one of those stats.

For the record, my Sport S Unlimited (3.6 auto) currently has 2700 km on the odometer and has been very gently driven (trying to respect the break in period).

Yesterday, it started with the an auto-stop/start not available error, then i got a battery warning light.
Called the dealer, and they told me to cycle the engine on and off and it would go away, and dont bring it in until it happens again.
I made a note of that, but decided that i would not go on any trips beyond 10Km from home for a while.

Today, i decided to risk it and take a small trip with the family over to Wal-mart down the road. Dropped them off at the door, and then when i went to pull into a parking spot, the Jeep started to shudder, and there was a message to "place vehicle in park then re-engage gear" or something like that.
I did that, and it seemed normal again except for the battery light being on.

I decided to chance it and immediately drive it home to get it back to my driveway, switch to my other SUV, and come back and pick up the family.
That did not work out, and i ended up stalling out in a busy intersection in the parking lot with my hazards on, so bad decision in retrospect.
I should mention that as it was cutting out, i got a series of very strange error messages... everything from "check airbags" to "transmission service".
After several attempts it just would not even turn over, so I called CAA and had it towed to the dealership, where it now sits.

I'm not going to lose faith for now, and hopefully this will be a quick one and done fix.. but we shall see :(
Hope i didnt make a bad buying choice here.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,284
Reaction score
2,415
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
@frajnai I am betting it’s a battery or IBS issue, several here have had batteries replaced, factory batteries regardless of who makes the vehicle don’t have a great reputation, kinda like the tires they put on new vehicles.

It’s honestly hard to say where they get there supply of batteries from and I’m sure these are not put on any bank chargers while they are waiting to be used then you have them making the trip from the maker and being jockeyed around and who knows if lights were left on or whatever that can drain a battery then if it does not start they toss a quick charge on long enough to get you out the door and take there chances if it will last or not.

I figure since I have a 4/48 extended warranty I will wait until it’s about up and start telling them that I have had to jump start it several times which after checking they may say it’s fine but I will have it on record about the battery and maybe after a few times of telling them this they will just replace both batteries to get me out the door and also by then maybe the batteries will be better but I’m not counting on that
 

drjhenrichs

Member
First Name
Jennifer
Joined
Dec 19, 2018
Messages
12
Reaction score
1
Location
Pearland
Vehicle(s)
2019 Jeep Rubicon
So, im hearing all these electrical gremlins, thinking ah well its just the internet. I mean i feel for all those people certainly, but i figure law of averages there will be a certain amount of issues and you are likely to hear about it on the internet.
Tonight i became one of those stats.

For the record, my Sport S Unlimited (3.6 auto) currently has 2700 km on the odometer and has been very gently driven (trying to respect the break in period).

Yesterday, it started with the an auto-stop/start not available error, then i got a battery warning light.
Called the dealer, and they told me to cycle the engine on and off and it would go away, and dont bring it in until it happens again.
I made a note of that, but decided that i would not go on any trips beyond 10Km from home for a while.

Today, i decided to risk it and take a small trip with the family over to Wal-mart down the road. Dropped them off at the door, and then when i went to pull into a parking spot, the Jeep started to shudder, and there was a message to "place vehicle in park then re-engage gear" or something like that.
I did that, and it seemed normal again except for the battery light being on.

I decided to chance it and immediately drive it home to get it back to my driveway, switch to my other SUV, and come back and pick up the family.
That did not work out, and i ended up stalling out in a busy intersection in the parking lot with my hazards on, so bad decision in retrospect.
I should mention that as it was cutting out, i got a series of very strange error messages... everything from "check airbags" to "transmission service".
After several attempts it just would not even turn over, so I called CAA and had it towed to the dealership, where it now sits.

I'm not going to lose faith for now, and hopefully this will be a quick one and done fix.. but we shall see :(
Hope i didnt make a bad buying choice here.

Let me know what they say. I’m having issues with the start stop, and my Jeep wants to act like it’s going to die on me. I keep seeing the same issue posts.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,284
Reaction score
2,415
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
Let me know what they say. I’m having issues with the start stop, and my Jeep wants to act like it’s going to die on me. I keep seeing the same issue posts.
Are you running any type of programmer
 

Martindfletcher

Well-Known Member
First Name
Martin
Joined
Jan 3, 2018
Messages
1,539
Reaction score
1,317
Location
San Diego
Vehicle(s)
Ducati 1299s, 2018 JLUR
No warning messages. ESS doesn't engage after about 8 months of vehicle ownership. I'm a light driver, but not so light that I feel it should affect ESS. I've never had battery issues with my other vehicles. I have a 24 x 7 dash cam that when in parking mode, but it would turn off if battery voltage drops below a 12V + threshold.

I checked fuses: fine, installed and energized a trickle charger, problem went away. Still have service call this week because maybe something's defective. I'd be upset to know that to save energy (read fuel) using ESS I have to expend energy (read: electric) to charge the rig on a regular basis. That seems self defeating to me.

Then again....problem may be something else that trickle charger is able to overcome the threshold of, that wouldn't be needed once repaired.

We'll see. Will report back.
Let us know. Mine goes into battery protection on long drives in high heat. I am not sure there is anything wrong. It always starts, as long as my fridge doesn’t kill it.
 

RussJeep1

Banned
Banned
Joined
Oct 12, 2016
Messages
2,548
Reaction score
1,931
Location
Westchester, NY
Vehicle(s)
JLU Sahara
Let us know. Mine goes into battery protection on long drives in high heat. I am not sure there is anything wrong. It always starts, as long as my fridge doesn’t kill it.

..wait...I don't like that this happens to you, I like the fact that you're sharing anecdotes in ways that can hone in on an answer.

Paradoxically enough, with significant engine "on time" intervals as you described, you'd think the batteries would be subjected to significant charge, were that the culprit to a non ESS engaging situation, and yet, in your case, possibly heat from the very friction and combustion that effects that charge may undermine it.

Interesting....
 

TimmH

Well-Known Member
First Name
Timm
Joined
Sep 18, 2018
Messages
619
Reaction score
683
Location
Florida
Vehicle(s)
2018 JL Wrangler Sahara 3.6 Auto
Vehicle Showcase
1
I noticed yesterday, after a couple days of colder weather, and I'm in South Florida, so it's not like we are talking sub-freezing, that my ESS was not operative for an entire 30 minutes drive. The message was that it was charging.
That has me a bit concerned for reliability of that battery and starting.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Messages
3,284
Reaction score
2,415
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
For all those getting the battery charging message I would get a meter and check voltages directly at the batteries, for checking the main you can use the -/+ posts off the main to check ESS voltage you will have to disconnect the ESS negative cable to isolate it or you will have a combined voltage of the main and ESS

Here is a voltage guide I have been using


67272FCD-4D29-4AA2-82CC-6BE288109487.jpeg
 
Last edited:

Martindfletcher

Well-Known Member
First Name
Martin
Joined
Jan 3, 2018
Messages
1,539
Reaction score
1,317
Location
San Diego
Vehicle(s)
Ducati 1299s, 2018 JLUR
..wait...I don't like that this happens to you, I like the fact that you're sharing anecdotes in ways that can hone in on an answer.

Paradoxically enough, with significant engine "on time" intervals as you described, you'd think the batteries would be subjected to significant charge, were that the culprit to a non ESS engaging situation, and yet, in your case, possibly heat from the very friction and combustion that effects that charge may undermine it.

Interesting....
Mine did it again yesterday, in 69 degree weather with about 90 minute drives, hour of wheeling, and heading home. I forgot to check it on way out.

It does act like it’s fully charged voltage drops from 14 to high 12 or 13 on throttle and it goes up off throttle like it’s saving fuel idleing the alternator.
 

eck

Well-Known Member
First Name
John
Joined
Dec 3, 2018
Messages
358
Reaction score
522
Location
Apex NC
Vehicle(s)
2018 JLU MOAB HellaYella
Mine went into battery protection mode yesterday. I left it on the trickle charger overnight and it seems to be fine today. I'll keep an eye on it and report back.
 

brazos

Well-Known Member
First Name
Joe
Joined
Apr 4, 2019
Messages
933
Reaction score
1,704
Location
Texas
Vehicle(s)
2018 JLU Sport, Giant singlespeed mountain bike, Hobie Revolution kayak
Occupation
Dog Feeder
Good to know that the worthless, expensive abomination shuts itself off rather than shutting the Jeep down when it fails.
 
Advertisement

Gibson Leatherworks
 
Advertisement
Top