Start stop not ready.

[jbehrn]

I looked through my old posts and found the tech’s solution:

Today I dropped it off my local dealer to have them take a look at it again. I was notified that the issue was that the ‘Intelligent Battery Sensor’ was not properly calibrated and didn’t know when the battery was charged. Because of the calibration issue the Start/Stop would not kick in. The tech had to recalibrate it and it’s working again.

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[Glad_he_ate]

My bet is on the battery being shit.
it started when the temps hit the 20s and has not recovered. While the truck is running it sits at 13.9 to 14.1 vdc. When the truck is off it quickly drops to 12.6….12.3….11.9 ….11.5 in a matter of a few min.

 

[ShadowsPapa]

My bet is on the battery being shit.
it started when the temps hit the 20s and has not recovered. While the truck is running it sits at 13.9 to 14.1 vdc. When the truck is off it quickly drops to 12.6….12.3….11.9 ….11.5 in a matter of a few min.

To clarify - you mean the voltage drops like that when the truck is OFF - meaning YOU shut it down?
Wow. That's bad. The batteries should sit at 12.6 for hours after a full shut-down.
Normal voltage ranges on these can be from about 12.7 to 14.6
That's what I've seen on mine over 2 years time.

My wife's Jeep battery voltages dropped down below 12 volts fairly quickly even after a full 24 hours of charging. Dealer said both batteries were bad.
I'd say you have bad batteries if it's running normal voltages when running but when you shut it off it drops that quickly.

 

[Glad_he_ate]

To clarify - you mean the voltage drops like that when the truck is OFF - meaning YOU shut it down?
Wow. That's bad. The batteries should sit at 12.6 for hours after a full shut-down.
Normal voltage ranges on these can be from about 12.7 to 14.6
That's what I've seen on mine over 2 years time.

My wife's Jeep battery voltages dropped down below 12 volts fairly quickly even after a full 24 hours of charging. Dealer said both batteries were bad.
I'd say you have bad batteries if it's running normal voltages when running but when you shut it off it drops that quickly.

Yes exactly. Shut the truck down with the off road pages on. And within minutes it’s dropped 2+volts. I’m a union electrician by trade, so it makes sense to me that I either have bad battery’s or a heavy draw keeping them down… my bets on the bad battery. This is what the warranty is for. I could take the time to find the issue but it’s not my job lol.

 

[Glad_he_ate]

Well I’m sitting here waiting on results…. They said up to 2 hrs to test EACH BATTERY really??

 

[Jeep-A-Kneez]

Yes exactly. Shut the truck down with the off road pages on. And within minutes it’s dropped 2+volts. I’m a union electrician by trade, so it makes sense to me that I either have bad battery’s or a heavy draw keeping them down… my bets on the bad battery. This is what the warranty is for. I could take the time to find the issue but it’s not my job lol.

Yeah, best let those folks do their job, else someone might file a grievance.

 

[Glad_he_ate]

Don’t want to step on the Dick of a fellow union worker!! The shop I’m at actually was just built last year and I was pleasantly surprised to find they used union labor. It’s not common to have union shops on private construction work.

 

[Glad_he_ate]

Aux battery replaced for dead cell.. battery charging Message was still there when I left dealer… drove 30 miles home and it’s still there called got the we so sorry nonsense and it’s going back next week because I don’t have time to take it back today. Not cool

 

[Jeep-A-Kneez]

Bummer

 

[Glad_he_ate]

Unfortunate they only go as far as finding A problem not THE problem…..

 

[slim chance]

dealer did a load test on main and aux batteries ... main tested good, aux failed the load test .. they ordered a new aux battery .. charged both batteries and said new aux battery would be there in about a week .. drove away from the load testing and ESS worked for 3 days straight even on cold mornings (around 35 degrees) waiting on new battery

 

[Glad_he_ate]

Well I might be alright. Drove over 100 miles today and on my way home the start stop changed to ready status. Perhaps it just needed x amount of ignition cycles to clear. Voltage is now changing based on load as it should. Turn the heat up blower comes on and it hits 14.5 turn the seats off and heat off and it sits at 12.9.. I’ll give it a couple days and call to cancel the appointment if it keeps working properly..

 

[centra28]

Thanks for this post. I just hit 10k miles and my start/stop hasnt been ready lately. Think I am going to have it checked out.

 

[Walter-new jeeper]

Earlier this year my aux battery died completely and the JT would not jump start at all because the aux battery was totally dead. Granted it had been sitting for a month because I could not drive due to surgery. But it should have charged up with a charger or at least be jumped. I had to have it towed to the service department.

End result - battery was dead due to bad engineering design. There is a water drain hole in the windshield wiper cowling that in the end drains into the battery box. At the bottom of the box is a drain hole. The drain hole got plugged when we had a snow storm and some debris fell in there causing the water to pool. The aux battery was sitting in this pool of water and it shorted out. Both batteries were replaced under warranty. And apparently due to the chaotic electronics while trying to get the vehicle started the radio lost the id info for sirius and gps. Had to get a new one put in - first replacement had an issue recognizing the antennas. Second replacement worked fine.

Who the heck designs the drainage path to go through the battery holder? An idiot engineer. Same type of engineer that designs a furnace such that you have to reach through the furnace through a 3 inch slot to remove and replace the air filters. When we had it replaced the technician cut a access door into the filter compartment so we could easily replace them. Engineer vs. a technician that has to service the furnace. Technician wins.

 

[Delhux]

If you happen to look, I'm guessing you have an "Early" MY21 JT. about late 3rd QT 2021 Mopar finally found a reliable battery for all the different AUX battery implications. Its been in all the new vehicles since and has been used to replace all if found bad.

You know if there was a technical service bulletin or something?

I took my truck in to be serviced for the ESS issue way too many times in 2020/2021.

They never did anything to fix it.

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