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Low charging or paranoid?

Terminus33

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Hi all, I think I may have an issue with my alternator or maybe the batteries and to tell you the truth it may have always been like this but I never noticed until I had a little freak out moment and started viewing the battery voltage page between my gauge clusters.

That little moment was while driving I came to a stop light and just when the ESS shut down the engine like always the whole Uconnect radio and all electrics turned off and I freaked out cause the light just turned green so I instinctively let off the brake and everything came on again like nothing happened. Off I go down the road as the radio booted like I turned the ignition off and back on.

This is the only time it has happened and the truck still drives normal and the ESS still functions as it should but I started monitoring the Voltage screen and these are what I get on average.

Stopped engine on 12.8v-13v
Driving steady speed 13v-13.3v
coasting to a stop 13v-14.2v
If I engage ESS and the engine shuts off I watch it go from ~13v down to 12.1v in about 10-15 seconds then I freak again and switch off ESS so the engine starts.

just wondering if it's normal for the voltage to go down to 12v or lower with ignition on and engine off at stops. I thought anything under 12.6 was a not fully charged battery. Am I worrying too much or should I take it to a dealer? I know it has one of them fancy "smart" alternators but didn't think it should drop that low.

Thanks guys for any input you may have.
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I would guess that there is still a load on the battery from the various electronics that remain active even though the engine stopped. That's my WAG.
 

Rollcast

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I checked my voltage a couple of times the last few days, and mine does the same. I wouldn't sweat over it.
 

CallMeJoe

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Mine drove me nuts for awhile. Local trips (my normal) always showed 14+. After a longer drive (1-2 hours) voltage drops to low 13's or even down to 12.9. let it sit for a day at home and it's back to 14-something. I'd say it's normal but it sometimes drives me nuts....
 

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Hi all, I think I may have an issue with my alternator or maybe the batteries and to tell you the truth it may have always been like this but I never noticed until I had a little freak out moment and started viewing the battery voltage page between my gauge clusters.

That little moment was while driving I came to a stop light and just when the ESS shut down the engine like always the whole Uconnect radio and all electrics turned off and I freaked out cause the light just turned green so I instinctively let off the brake and everything came on again like nothing happened. Off I go down the road as the radio booted like I turned the ignition off and back on.

This is the only time it has happened and the truck still drives normal and the ESS still functions as it should but I started monitoring the Voltage screen and these are what I get on average.

Stopped engine on 12.8v-13v
Driving steady speed 13v-13.3v
coasting to a stop 13v-14.2v
If I engage ESS and the engine shuts off I watch it go from ~13v down to 12.1v in about 10-15 seconds then I freak again and switch off ESS so the engine starts.

just wondering if it's normal for the voltage to go down to 12v or lower with ignition on and engine off at stops. I thought anything under 12.6 was a not fully charged battery. Am I worrying too much or should I take it to a dealer? I know it has one of them fancy "smart" alternators but didn't think it should drop that low.

Thanks guys for any input you may have.
Take it to a dealer and have the system checked and the batteries tested. The auxiliary (ESS) battery is there to keep the computers stable during ESS events. I have seen the voltage drop down to 12.3 during an ESS stop, but I usually have ESS turned off. I have never had my Uconnect reboot while driving or when the ESS kicks in, it is not supposed to.
 
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jebiruph

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Hi all, I think I may have an issue with my alternator or maybe the batteries and to tell you the truth it may have always been like this but I never noticed until I had a little freak out moment and started viewing the battery voltage page between my gauge clusters.

That little moment was while driving I came to a stop light and just when the ESS shut down the engine like always the whole Uconnect radio and all electrics turned off and I freaked out cause the light just turned green so I instinctively let off the brake and everything came on again like nothing happened. Off I go down the road as the radio booted like I turned the ignition off and back on.

This is the only time it has happened and the truck still drives normal and the ESS still functions as it should but I started monitoring the Voltage screen and these are what I get on average.

Stopped engine on 12.8v-13v
Driving steady speed 13v-13.3v
coasting to a stop 13v-14.2v
If I engage ESS and the engine shuts off I watch it go from ~13v down to 12.1v in about 10-15 seconds then I freak again and switch off ESS so the engine starts.

just wondering if it's normal for the voltage to go down to 12v or lower with ignition on and engine off at stops. I thought anything under 12.6 was a not fully charged battery. Am I worrying too much or should I take it to a dealer? I know it has one of them fancy "smart" alternators but didn't think it should drop that low.

Thanks guys for any input you may have.
This is normal operation. Voltage goes up to help charging during deceleration and the ESS voltage drop is the switch over from alternator power to battery power.
 

CrazyCooter

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Yes, this smart alternator is a pita especially for people the do shorter trips. It doesn't charge trailer batteries either.....

I just installed a 30w solar panel on my hood to help with running my fridge and top off the batteries. The voltage from this weekend still at 12.25 resting as I have not wired the charge controller yet.
 

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Hi all, I think I may have an issue with my alternator or maybe the batteries and to tell you the truth it may have always been like this but I never noticed until I had a little freak out moment and started viewing the battery voltage page between my gauge clusters.

That little moment was while driving I came to a stop light and just when the ESS shut down the engine like always the whole Uconnect radio and all electrics turned off and I freaked out cause the light just turned green so I instinctively let off the brake and everything came on again like nothing happened. Off I go down the road as the radio booted like I turned the ignition off and back on.

This is the only time it has happened and the truck still drives normal and the ESS still functions as it should but I started monitoring the Voltage screen and these are what I get on average.

Stopped engine on 12.8v-13v
Driving steady speed 13v-13.3v
coasting to a stop 13v-14.2v
If I engage ESS and the engine shuts off I watch it go from ~13v down to 12.1v in about 10-15 seconds then I freak again and switch off ESS so the engine starts.

just wondering if it's normal for the voltage to go down to 12v or lower with ignition on and engine off at stops. I thought anything under 12.6 was a not fully charged battery. Am I worrying too much or should I take it to a dealer? I know it has one of them fancy "smart" alternators but didn't think it should drop that low.

Thanks guys for any input you may have.
Normal. I've watched mine drop to below 12 volts. Freaked me out at first being a long-time auto tech specializing in electric. Used to be a fully charged battery was 12.6 and normal charging voltage - operating voltage while running was 13.8 - 14.2
But I've seen well over those numbers and well under those numbers. And mine seems fine.
Since it's not a "regulated output" system where it maintains a constant voltage no matter what, just have to ignore what we knew.
 

ShadowsPapa

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PS - I was always told it's not paranoia if someone really IS following you.......... so maybe you aren't paranoid after all........
 

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Apparently its normal for the Gladiator, and we should be concerned primarily if a battery icon shows up while driving. I received two charging system email warnings now, but had two dealerships say everything is normal. Highway driving is 12.7-12.9V... coasting or braking and it jumps to 14.X. I always turn off ESS.
 

CrazyCooter

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I got an email a couple of days ago about a charging system issue, but I had left my dump trailer hooked up and was dumping and shoveling it over a couple of days. Surely doesn't help that voltage when parking is 12.4ish. No wonder there are so many battery failures?

I installed the Cascadia 4x4 30w hood solar panel, but its proving to be pretty much a waste of money in our climate. Max I've seen under normal conditions is 3 watts output, but drops to 1 watt pretty much as soon as the sun raises the panel temp. Start the Jeep and add engine heat.....forget about getting any output. Hit it with a garden hose and it maxes out at 9 watts, but drops back down to 1 watt in a few min as it warms up.
 

ShadowsPapa

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Apparently its normal for the Gladiator, and we should be concerned primarily if a battery icon shows up while driving. I received two charging system email warnings now, but had two dealerships say everything is normal. Highway driving is 12.7-12.9V... coasting or braking and it jumps to 14.X. I always turn off ESS.
We used to consider a fully charged normal battery as being 12.6 volts. If the JT system is showing 12.7 or better, it means it's keeping ahead of demand and the battery needs.
If I saw 12.5, I'd be concerned. 12.6 might make me wonder if it was having trouble staying cool.

I saw temperatures of 230 on this trip - but everything was working absolutely perfectly - AC, lights, everything. No errors, ESS worked fine. This was taken over a month ago and it's still fine ->

Jeep Gladiator Low charging or paranoid? 20210613_150145
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