Your battery voltage - truck off and at rest

[ShadowsPapa]

Oh, I completely understand. But, IMO it is very important for everyone reading your replies to understand that just because you found some information on the internet and regurgitated it here does not mean that you actually know it.

I use what I already know to start with, and verify it if necessary. I do that from tech docs I have, and if it's info from the web, I cross check that against other sources. Some of the info is from Bosch, Vishay Intertechnology, etc.

I love automotive electric system work, I got started when the HS instructor tagged me for that spot in for the Plymouth Troubleshooting contest and decided I loved it. So this stuff fascinates me and I dig hard to learn more.

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[chorky]

So are you trying to maintain the proper functioning of the aux battery system? If it's giving so much trouble why not just eliminate it entirely - unless one uses and enjoys ESS

 

[ShadowsPapa]

So are you trying to maintain the proper functioning of the aux battery system? If it's giving so much trouble why not just eliminate it entirely - unless one uses and enjoys ESS

There's no "enjoying" to it - it saves us gas (and that's proven so let's not get into the religious bits about the hate of ESS)

I'm trying to maintain the correct functionality of the truck. The ESS is a SYMPTOM that showed there's a problem keeping the battery voltage up. Nothing to do with the "aux battery system".
An AGM battery voltage of 12.19 is low. In fact, Nissan actually says this:
Any battery whose SOC is found below a minimum of 12.4V should be charged and confirmed “OK” before delivering to a customer. Any batteries that are below 12.0V indicate the battery is not recoverable to 100% State of Charge and it should be replaced.

I find that a bit extreme, personally, but then after seeing my own behave, I am wondering........

To recap:
AGM batteries fully charged should be sitting at over 12.6 - typically 12.7-12.8.
That's a battery that's fully charged.
A battery that's sitting at 12.19 volts is ~50% charge, depending on who's chart you use (anything from ~50 to ~60%) (' ~ ' means "about" or "roughly")

.........indicating that after driving my truck for a combined total of 90 minutes, the next day my truck batteries are sitting only ~50 to 60% charged, if you are an optimist, that's 70% charge, still less than 3/4 fully charged.
Doing that for roughly 2 or 3 years cuts the battery life way down. AGM are really bad but frankly any storage battery is going to have a lower life if it's not properly maintained and charged.

The ESS message of ".........not ready, battery charging" for months was telling me something is amiss.

I found my truck's batteries are never getting charged even to the point of being able to do a proper load test. As the tech said - he had to charge the batteries before he could even test them. After driving the truck from home clear up to another city where the dealership is, it was too low to load test. (minimum required SoC is 12.4 volts)

My 'guess' is the IBS - if that's going goofy, or has issues, battery life is shortened a fair amount and there could come a time the vehicle simply won't start.

So it's not about ESS, ESS is a symptom of other things going on and is what alerted me to a possible problem. And yes, there's the gas mileage bit when you sit 180 seconds at a light with the engine running. But this isn't about politics, hate, EPA, etc..
Oddly, the 4.0 in my Eagle will trigger a MIL if the battery voltage gets too low, like under 12.0 volts (conventional battery). I've seen my truck sit at high 11's before. And no error message.

 

[Erievon]

So are you trying to maintain the proper functioning of the aux battery system? If it's giving so much trouble why not just eliminate it entirely - unless one uses and enjoys ESS

I almost always turn off ess. But it's under warranty, it should be correct. If it was out of warranty sure, I'd probably buy an Optima, bypass the aux batt and go about my way. But even the main is struggling right now which really concerns me.

 

[ShadowsPapa]

I almost always turn off ess. But it's under warranty, it should be correct. If it was out of warranty sure, I'd probably buy an Optima, bypass the aux batt and go about my way. But even the main is struggling right now which really concerns me.

Another good point - its under warranty and picky silly me expects things to work correctly while it's still under warranty. I'm odd that way, I guess.

A side topic on batteries I find interesting - Optima and other battery companies say when charging multiple batteries, only charge the in pairs if they are the same capacity and approximate age, and yet.........
MOPAR/Jeep is violating the rules set by the battery companies in that they are two different battery sizes, and, when people do the swapping, changing the setup and all that, one or both rules of charging are broken again.
Damn, again I took a side road........

 

[Maximus Gladius]

Let’s say you change out the main battery for lithium and leave the small AGM battery… your saying there’s going to be a problem with the charging right? I think the only answer is to remove the AGM and install duel battery system.

 

[ShadowsPapa]

Let’s say you change out the main battery for lithium and leave the small AGM battery… your saying there’s going to be a problem with the charging right? I think the only answer is to remove the AGM and install duel battery system.

Batteries of different capacities and ages and types charge at different rates - and voltages. The IBS is likely, in conjunction with the PCM, programmed to optimize the charging voltage and rate for the batteries from the factory. Like the folks on the BMW forum said to the guy who removed is IBS - 'good luck'.........
The larger battery will charge more slowly than the smaller battery, once the small one is charged if they keep up the rate to finish off the larger battery, they risk heating up the smaller battery. (that's how Optima and other battery manufacturers explain it) Similar for different types. To charge a standard lead/acid battery with the AGM voltages would cook the standard wet battery.
Frankly, I can't see how they manage it with batteries of different sizes in parallel. But I've not put a lot of thought into it, not seen the actual size or capacity of the smaller aux battery.
And there's no way in heck I'd replace one and not the other and really for sure no way I'd put a different type in place and leave the other.
In the end, I have no interest in changes, I want it working as designed. I have no need for any other system anyway. It is under warranty, it's up to them to fix it.

I have the ear of the dealership I bought the truck from, so maybe, there's actually someone who knows what they are doing out there.
I will try resetting the IBS this week - it's a simple matter, it just takes a lot of time for it to relearn.
Funny thing - I have not received an email about completing a survey after this last visit ... hmmmm.

 

[chorky]

There's no "enjoying" to it - it saves us gas (and that's proven so let's not get into the religious bits about the hate of ESS)

I'm trying to maintain the correct functionality of the truck. The ESS is a SYMPTOM that showed there's a problem keeping the battery voltage up. Nothing to do with the "aux battery system".
An AGM battery voltage of 12.19 is low. In fact, Nissan actually says this:
Any battery whose SOC is found below a minimum of 12.4V should be charged and confirmed “OK” before delivering to a customer. Any batteries that are below 12.0V indicate the battery is not recoverable to 100% State of Charge and it should be replaced.

I find that a bit extreme, personally, but then after seeing my own behave, I am wondering........

To recap:
AGM batteries fully charged should be sitting at over 12.6 - typically 12.7-12.8.
That's a battery that's fully charged.
A battery that's sitting at 12.19 volts is ~50% charge, depending on who's chart you use (anything from ~50 to ~60%) (' ~ ' means "about" or "roughly")

.........indicating that after driving my truck for a combined total of 90 minutes, the next day my truck batteries are sitting only ~50 to 60% charged, if you are an optimist, that's 70% charge, still less than 3/4 fully charged.
Doing that for roughly 2 or 3 years cuts the battery life way down. AGM are really bad but frankly any storage battery is going to have a lower life if it's not properly maintained and charged.

The ESS message of ".........not ready, battery charging" for months was telling me something is amiss.

I found my truck's batteries are never getting charged even to the point of being able to do a proper load test. As the tech said - he had to charge the batteries before he could even test them. After driving the truck from home clear up to another city where the dealership is, it was too low to load test. (minimum required SoC is 12.4 volts)

My 'guess' is the IBS - if that's going goofy, or has issues, battery life is shortened a fair amount and there could come a time the vehicle simply won't start.

So it's not about ESS, ESS is a symptom of other things going on and is what alerted me to a possible problem. And yes, there's the gas mileage bit when you sit 180 seconds at a light with the engine running. But this isn't about politics, hate, EPA, etc..
Oddly, the 4.0 in my Eagle will trigger a MIL if the battery voltage gets too low, like under 12.0 volts (conventional battery). I've seen my truck sit at high 11's before. And no error message.

Maybe I struck a nerve but was not intending to get into an argument of politics, or EPA stuff or whatever.. Personally I dislike it either way but also live in a very rural area with one stop sign within a hour drive. Just was simply suggesting to consider options that remove the Aux battery, and thus ESS from the equation. Not that doing so would even resolve issue of not fully charging batteries. Anyway I do hope you get it figured out and it will be interesting to see what the final culprit was. Having engineered equipment not function as design is frustrating to say the least. Have you considered checking for parasitic drain? I mean it is pretty clear that the system isn't charging the batteries enough anyway - but it might not hurt to check?

What do you mean by "AGM is really bad..." Are you talking about their lifespan or just in general?

I almost always turn off ess. But it's under warranty, it should be correct. If it was out of warranty sure, I'd probably buy an Optima, bypass the aux batt and go about my way. But even the main is struggling right now which really concerns me.

Yeah and that's a good point being under warranty. I suppose it's hard to say anymore these days what would and would not void a warranty for any particular issue. But why is that holding you off from getting an Optima?

Another good point - its under warranty and picky silly me expects things to work correctly while it's still under warranty. I'm odd that way, I guess.

A side topic on batteries I find interesting - Optima and other battery companies say when charging multiple batteries, only charge the in pairs if they are the same capacity and approximate age, and yet.........
MOPAR/Jeep is violating the rules set by the battery companies in that they are two different battery sizes, and, when people do the swapping, changing the setup and all that, one or both rules of charging are broken again.
Damn, again I took a side road........

Yeah and this is a very interesting and good point. It makes me really think that part of the whole thing is kinda, well, weird. Not to go down that road, but engineers must know that two batteries of different capacities charge at different rates and without some type of in-line restrictor, or a DC/DC charger the system will surely kill one battery sooner than it should by either over or under charging. Or maybe not by some weird design of wire sizing and length with calculated voltage drops. It is, to me, a pretty weird design in the first place though. It would make more sense if the two batteries were the same size. But it is odd for it to not function or even be able to charge the main battery after a drive over an hour long.

 

[Gren71]

At what point should a battery be changed? Im 64,000+ miles in And wondering if it may just be time to swap for a new battery.

 

[kahuna357]

Another good point - its under warranty and picky silly me expects things to work correctly while it's still under warranty. I'm odd that way, I guess.

I just read through this whole thread and agree with you @ShadowsPapa. I have a 2021 that is 17 months old and approximately 8500 miles. I noticed that about my ESS was not activating/working regularly about 3 months ago. My message only says "Not Ready" does say anything about battery charging. I noticed that after a drive of 40+ miles it will work for a couple a day and then back to not working. I have not measure the battery voltage directly as mentioned here but what I did was used the off road gauge pages app and monitor the engine temp, oil temp, battery voltage, trans temp and outside temp to see if there was any correlation between the numbers. What I noticed was the only thing that mattered was that the battery voltage had to hold steady at 14.4 volts or higher. Nothing else other than engine temp affects wether ESS works or not. I also noticed that after 30 or 40 mile drives that the voltage reading would go as high as 14.7 and the ESS would work for more days. Now the highest it will go is 14.4 and I get maybe 2 or 3 days of around town driving before "Not Ready" comes back. As much as I hate all the dealerships around me I think it's time to make an appointment to see what kind of nonsense they tell me.

 

[ShadowsPapa]

What do you mean by "AGM is really bad..." Are you talking about their lifespan or just in general?

Can't find where I said that...............

must be on another page?

They are bad as far as needing the proper charging and about being allowed to sit with a low charge.

I checked battery voltage before our outing today at 4pm. Voltage was down to 12.34 (again, yes, it's true - that's fully connected in the truck)
We took off and I watched the display for auto stop/start and it said "cabin heating/cooling". It was very windy (40 mpg gusts) and 39 degrees, we had the HVAC set to auto and 68 degrees.
We got 3 miles from home and suddenly the display said stop/start ready, and it worked at the next stop sign, 3.5 miles from home. It worked the whole trip out, shopping, and back home. Voltage when I got home was 12.4
Weird but then the system tracks total battery health, history, use, charge and more to determine if there's enough capacity to restart once ESS shuts it down and apparently at 12.4 volts it decided there was enough capacity (obviously as the truck starts easily at 12.19 volts)

 

[chorky]

About the AGM I was asking because I couldn't understand the context of the sentence. It was a few pages back probably, but anyway, man thats frustrating. I understand your wanting to have it working properly because that's what it's there for. I just purchased my Glad yesterday. When I drove off the lot for a test drive it said 'not ready' also. I think I tested voltage this morning on the main battery at 12.6 if memory is right. Leaving ESS on for a 4 hour joy ride today it finally cut the engine at a stopsign somewhere along the way - that was 2 hours into the drive. No doubt I will be experiencing similar issues as you.

So did you test the voltage with a meter when you got home or just the vehicle's systems? I would be curious to see how much voltage drops over the night - and will probably go check mine right now and see as well. Not that it's any bit of a good excuse but the standby systems can't be great for the battery over a period of time.

Edit:
For reference if it helps mine is sitting at 12.79 right now.

 

[Erievon]

it's hard to say anymore these days what would and would not void a warranty for any particular issue. But why is that holding you off from getting an Optima?

Well...it's under warranty, why should I pony up that kind of money for a battery that is covered?

 

[Gren71]

Well...it's under warranty, why should I pony up that kind of money for a battery that is covered?

Are batteries covered under the factory warranty? They seem like an item thats more in line with breaks and such. So as to say that after a special amount of time they can/will fail and the warranty won’t cover them. I didn’t check my aftermarket warranty yet but i feel like i read they aren’t covered unless they fail catastrophically early on.

 

[chorky]

Well...it's under warranty, why should I pony up that kind of money for a battery that is covered?

Agreed. they are I think for 3 years? I thought you were venturing to say that putting n an Optima would somehow void any warranty work of the charging system. But yeah I agree, if its a failure should be warrantied.

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