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Your battery voltage - truck off and at rest

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ShadowsPapa

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These have some small "always on" systems, but they also have some that do "polling" meaning they are off, only coming on at quick intervals to check to see if any action is needed and then they are off again.

I seem to have lost the file but I had a document on IBS that even said it was more of a polling thing when the engine was off, waking up on occasion to check the state of things, then sleeping again.
Really wish I could find that.

I don't want to end up resetting things again or I'd put my Fluke in line and measure the draw.

The USB ports continue to supply power if an active device is connected.
Not mine. They go to sleep after about 60 minutes. I found that out when I tried to use my truck to charge my hearing aids and left my phone connected. I went out and found everything off, and had to go into run mode, then off again and bought more time, then went back out and did it again. Even the book said ->
The Smart Charging USB ports provide power to your device
up to an hour after the vehicle is turned off.
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These have some small "always on" systems, but they also have some that do "polling" meaning they are off, only coming on at quick intervals to check to see if any action is needed and then they are off again.

I seem to have lost the file but I had a document on IBS that even said it was more of a polling thing when the engine was off, waking up on occasion to check the state of things, then sleeping again.
Really wish I could find that.

I don't want to end up resetting things again or I'd put my Fluke in line and measure the draw.



Not mine. They go to sleep after about 60 minutes. I found that out when I tried to use my truck to charge my hearing aids and left my phone connected. I went out and found everything off, and had to go into run mode, then off again and bought more time, then went back out and did it again. Even the book said ->
The Smart Charging USB ports provide power to your device
up to an hour after the vehicle is turned off.
I thought about doing current draw test but I wonder if you will get an accurate reading disconnecting the cable from the battery to put the meter in series? Would the truck have to go into a running cycle then back off to see the true "at rest" current draw from all the systems?
 
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I thought about doing current draw test but I wonder if you will get an accurate reading disconnecting the cable from the battery to put the meter in series? Would the truck have to go into a running cycle then back off to see the true "at rest" current draw from all the systems?
To me the problem is that the batteries are connected in parallel - so you'd have to put the meter in such a place as to measure the draw from both. If you put a meter between the top of the IBS and the cables connected to it, the aux battery can feed the electronics and nothing come from the main battery. Similar for the positive lead, so you 'd have to place the meter so it could read anything coming from both/either.
Easiest may be to take the aux battery out of the equation by taking the aux battery ground cable off the top of the IBS.
 
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So now this is getting really silly. Drove the truck around picking up plywood on Tuesday.
(1/2 sheet of 1/2" and 1/2 sheet of 3/4" - 100 bucks)

The truck sat unused Wednesday and Thursday. This is Friday - this AM I took the truck to Altoona for some supplies (damn sparrows), that's all but 12 miles each way. It was 37 degrees out.
Auto stop/start not ready, battery charging - and - voltage a fairly solid 14.7 all the way up (almost 12 miles) AND all the way back - another almost 12 miles. So I'll call it 23 miles round-trip.
23 miles, 14.7 volts, not ready, battery charging. That makes ESS pretty much dead for ordinary drivers.

Ah, but wait, there's more! I checked battery voltage when I got back! That's 20 minutes driving up and 20 minutes driving back, 23 miles total. This is after I got back - Put on the reading glasses, that's 12.2 (TWELVE POINT TWO) Volts AFTER 40 minutes of driving.
No, I didn't check it before I left, really wish I had)

Jeep Gladiator Your battery voltage - truck off and at rest 20220415_120844


Now what's the state of charge on two batteries sitting in parallel at 12.2 volts?

Try 48% according to this (and some charts as well)
Reading glasses again ->

Jeep Gladiator Your battery voltage - truck off and at rest 20220415_120805


So, before I even left the garage, the batteries were UNDER 50% and most likely well under 12.2 volts since that 12.2 is after returning home, driving 2 times 20 minutes (23 miles)
You're telling me that a 240 amp alternator running 14.7 volts can't keep these tiny batteries charged?
And - that sitting 2 days drains 50% SoC off the top?

It appears that after charging both batteries twice - independently each time, reconnecting them, charging again, and driving it around and things are fine, that once it sits for a day, things go down the toilet.
The goofy thing is that the sort of voltage applied, and the 240 amp capability of an alternator can't keep up with use, or, these things aren't truly ever being totally charged.......... is that right?
And that sitting, either the batteries are so bad that they drop 50% in 2 days, or there's such a huge drain somewhere that empties them as it sits..................
I give it another few days then I contact a different dealership and show them everything that's been done, all measurements, checks, battery charges and so on.
 

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Did you decide to trade your truck yet?? Drove mine all week to work and back (literally a 3 minute drive) just because I was lazy and heated seats are nice. Anyway, each day when I get to the only stop sign, maybe 1.5 minutes after leaving the house (but I do let it 'warm up' for about 15 minutes since short start/stop cycles aren't that good) the ESS kicks in and cuts the engine. Even when it's 28 outside, and with short cycles so it's probably barely recharging in the 3 minute drive.

I feel your pain but man something with that rig is just not right. What it is who knows. Maybe you can warranty out the batteries and see if one of them has gone bad causing the problem?
 

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Oh and I wish I had those plywood prices. over 100 bucks a sheet here at the moment. :-/ - well last time I looked anyway.
 
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Oh and I wish I had those plywood prices. over 100 bucks a sheet here at the moment. :-/ - well last time I looked anyway.
It's 85 per full sheet but I needed 2 different sizes so bough half sheets making it slightly more expensive. A cost of convenience. This old fart didn't have to carry full sheets of plywood upstairs to my wood shop to be cut to size and shape, etc. That 2nd story of my shop is over 15' up.

Anyway, yeah, when I was driving it every day, just after all of the battery charging, for several days it all worked fine - ESS worked, and voltages were at least above 12.5 (12.4 appears to be some sort of cut-off point for ESS)

I will see if there's more info to gather, that sort of thing, but I've had one dealer look at it and claim my winch was draining the batteries (they don't know how OFF switches, or a big red disconnect button works?) and said there's nothing wrong. But then it was the same guy that said Jeep ABS and TC don't work under 35 mph which is total BS, too.......... so it will be a different dealer next time.
 

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So now this is getting really silly. Drove the truck around picking up plywood on Tuesday.
(1/2 sheet of 1/2" and 1/2 sheet of 3/4" - 100 bucks)

The truck sat unused Wednesday and Thursday. This is Friday - this AM I took the truck to Altoona for some supplies (damn sparrows), that's all but 12 miles each way. It was 37 degrees out.
Auto stop/start not ready, battery charging - and - voltage a fairly solid 14.7 all the way up (almost 12 miles) AND all the way back - another almost 12 miles. So I'll call it 23 miles round-trip.
23 miles, 14.7 volts, not ready, battery charging. That makes ESS pretty much dead for ordinary drivers.

Ah, but wait, there's more! I checked battery voltage when I got back! That's 20 minutes driving up and 20 minutes driving back, 23 miles total. This is after I got back - Put on the reading glasses, that's 12.2 (TWELVE POINT TWO) Volts AFTER 40 minutes of driving.
No, I didn't check it before I left, really wish I had)

20220415_120844.jpg


Now what's the state of charge on two batteries sitting in parallel at 12.2 volts?

Try 48% according to this (and some charts as well)
Reading glasses again ->

20220415_120805.jpg


So, before I even left the garage, the batteries were UNDER 50% and most likely well under 12.2 volts since that 12.2 is after returning home, driving 2 times 20 minutes (23 miles)
You're telling me that a 240 amp alternator running 14.7 volts can't keep these tiny batteries charged?
And - that sitting 2 days drains 50% SoC off the top?

It appears that after charging both batteries twice - independently each time, reconnecting them, charging again, and driving it around and things are fine, that once it sits for a day, things go down the toilet.
The goofy thing is that the sort of voltage applied, and the 240 amp capability of an alternator can't keep up with use, or, these things aren't truly ever being totally charged.......... is that right?
And that sitting, either the batteries are so bad that they drop 50% in 2 days, or there's such a huge drain somewhere that empties them as it sits..................
I give it another few days then I contact a different dealership and show them everything that's been done, all measurements, checks, battery charges and so on.
I've been seeing drops of 5-7% overnight (14 hrs). I'mo getting very close to putting a shunt meter on mine to see how much current this thing is drawing "at rest". Some quick calculations tell me it drawing and average of .5 amps over night. Crazy.
 

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The fact that mine is acting exactly like Papa's, we either all got a really crappy batch of batteries, or the charging system has a flaw in it somewhere.
 

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I've been seeing drops of 5-7% overnight (14 hrs). I'mo getting very close to putting a shunt meter on mine to see how much current this thing is drawing "at rest". Some quick calculations tell me it drawing and average of .5 amps over night. Crazy.
Considering all the electronics on these things I dont think that is something that's exceptionally out above possibilities.
 

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I've been seeing drops of 5-7% overnight (14 hrs). I'mo getting very close to putting a shunt meter on mine to see how much current this thing is drawing "at rest". Some quick calculations tell me it drawing and average of .5 amps over night. Crazy.
I'd love to see the results. That's way over what someone else said the draw should be - it was less than half that number if I recall - and if THEY were correct.
 

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From what I have read, modern vehicles should draw no more than .05 amps (50 milliamps) while "at rest/sleeping".
 
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From what I have read, modern vehicles should draw no more than .05 amps (50 milliamps) while "at rest/sleeping".
That's actually pretty close to what I've heard, never got back to deeper investigating, but that sounds close. Some stuff isn't actually "Awake", but wakes periodically to poll, so it cuts the actual draw quite a bit. On some systems, even the IBS main circuit sleeps, and wakes periodically to check on draw, battery temp and condition, then goes back to sleep.

If your number (and what I've heard) is accurate, it would take a lot more than a week to drain a good battery.
 

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That's actually pretty close to what I've heard, never got back to deeper investigating, but that sounds close. Some stuff isn't actually "Awake", but wakes periodically to poll, so it cuts the actual draw quite a bit. On some systems, even the IBS main circuit sleeps, and wakes periodically to check on draw, battery temp and condition, then goes back to sleep.

If your number (and what I've heard) is accurate, it would take a lot more than a week to drain a good battery.
I totally agree.
Another thing to keep in mind with the alternator charging...I put mine in a charger after sitting for a few days. Voltage was down around 12.2. it took 3-4 hours or so to get to full charge.

When I get the battery charging message the dash meter is usually stuck around 13.8-14.0 volts. I haven't had the opportunity or time to see how long you have to drive to let the system charge itself and make everything happy.
 
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I totally agree.
Another thing to keep in mind with the alternator charging...I put mine in a charger after sitting for a few days. Voltage was down around 12.2. it took 3-4 hours or so to get to full charge.

When I get the battery charging message the dash meter is usually stuck around 13.8-14.0 volts. I haven't had the opportunity or time to see how long you have to drive to let the system charge itself and make everything happy.
Based on the meta info in the pics (and the file names), I put the charger on at 12:08 today.
The charger was in completion mode, constant 12.7 volts, amperage ramping down by 3:50 pm, about 4 hours later. So it was basically done. It's in rest mode now, sitting charged 100%, voltage at 12.7 volts. So it didn't really take all that long to get a full charge, and that's both batteries since when the truck is off and sitting, they are connected together in parallel.
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