New Aux battery, ESS light now on, can't clear

[Sixt7gt350]

What were the battery voltage readings after charging, would be my first question? My next question would be, did you verify that your Fuse array is good? If all that is good, I would check for a battery drain.

I didn't measure the voltage after charging. Both batteries are new, both charged to "100%" when I had them and the IBS disconnected.
So frustrating, no lights until after the new aux battery.

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[Sixt7gt350]

You can charge a worn-out battery all you want. You can't make it new.

Both batteries brand spanking new.

 

[Lost1wing]

I would start testing the fuse array.

 

[Andy29847]

What does your onboard volt meter show when you are driving around?

 

[Andy29847]

This drawing, from member Jebiruph, is one I refer to when participating in threads like these. This is the best illustration I have seen regarding the Jeep dual battery system.

You need to determine if you are having battery problems, charging problems, or system problems. I suggest starting over with your testing. The first step would be disconnect the batteries from each other, allow them to sit for several hours (to bleed off surface charge), and then test each battery. New, fully charged batteries should test ~12.8vdc. Both batteries should test the same.

Here is info for the IBS reset procedure:
IBS > Clear/Reset:
IBS Sensor: Mopar 68289207AC

Disconnect all 12v power to the JL/JT *

Now, when 12v power is restored, the IBS starts a lengthy relearn process.

Until the relearn process is complete, accurate battery state (MAIN battery) information is unavailable to other vehicle systems.

This relearning process requires 5 normal, operator initiated starts with at least eight hours off time between each start. Usually, the process takes a few days of vehicle operation to complete.

Important: The relearning process is restarted every time power is reconnected to the IBS after a complete 12v power disconnection in regard to the vehicle. This has a major effect on the stop/start feature. (ESS)

Important: You can also, with vehicle turned off... just unplug the IBS, leave it unplugged for a few minutes and then plug IBS back in and this will also restart the relearning process.

Charging voltage on my Jeeps as read on the dash voltmeter varies a great deal. I would expect charging voltage after an IBS reset to be ~14.7vdc.

 

[Sixt7gt350]

This drawing, from member Jebiruph, is one I refer to when participating in threads like these. This is the best illustration I have seen regarding the Jeep dual battery system.

You need to determine if you are having battery problems, charging problems, or system problems. I suggest starting over with your testing. The first step would be disconnect the batteries from each other, allow them to sit for several hours (to bleed off surface charge), and then test each battery. New, fully charged batteries should test ~12.8vdc. Both batteries should test the same.

Here is info for the IBS reset procedure:
IBS > Clear/Reset:
IBS Sensor: Mopar 68289207AC

Disconnect all 12v power to the JL/JT *

Now, when 12v power is restored, the IBS starts a lengthy relearn process.

Until the relearn process is complete, accurate battery state (MAIN battery) information is unavailable to other vehicle systems.

This relearning process requires 5 normal, operator initiated starts with at least eight hours off time between each start. Usually, the process takes a few days of vehicle operation to complete.

Important: The relearning process is restarted every time power is reconnected to the IBS after a complete 12v power disconnection in regard to the vehicle. This has a major effect on the stop/start feature. (ESS)

Important: You can also, with vehicle turned off... just unplug the IBS, leave it unplugged for a few minutes and then plug IBS back in and this will also restart the relearning process.

Charging voltage on my Jeeps as read on the dash voltmeter varies a great deal. I would expect charging voltage after an IBS reset to be ~14.7vdc.

The only thing I didn't do, since the batteries are brand new, was measure voltage after charging and measure again after sitting.
I was counting starts with at least 8 hours between, yesterday afternoon was number 6. (Teleconference Wednesday, so only 7 hours between commute starts that day)

"normal, operator-initiated"
Are you saying the system won't learn if remote started?

Charging voltage at idle was measured before the IBS reset at 14.5 (obd reader)​

 

[Andy29847]

"normal, operator-initiated"
Are you saying the system won't learn if remote started?

Charging voltage at idle was measured before the IBS reset at 14.5 (obd reader)​

I do not know the answer to the remote start question. I'd expect that a "remote start" is the same as an "operator-initiated" start.


If it were me, I'd be inclined to delete the aux battery by disconnecting (and insulating the end) the negative battery cable for the aux battery at the main battery terminal. You should then pull fuse F42 to disable the power control relay. Your Jeep should operate the same on one battery as it does on 2.

Did you use the Walmart Everstart H7 premium battery when you replaced the main battey?

The number of starts you are initiating are different than how I have used my Jeep. How long does the Jeep run between stops.

 

[Sixt7gt350]

I do not know the answer to the remote start question. I'd expect that a "remote start" is the same as an "operator-initiated" start.


If it were me, I'd be inclined to delete the aux battery by disconnecting (and insulating the end) the negative battery cable for the aux battery at the main battery terminal. You should then pull fuse F42 to disable the power control relay. Your Jeep should operate the same on one battery as it does on 2.

Did you use the Walmart Everstart H7 premium battery when you replaced the main battey?

The number of starts you are initiating are different than how I have used my Jeep. How long does the Jeep run between stops.

ACDelco aux on 11Jan
EverStart platinum H7 on 12Jan
Full disconnect and full offboard charge 18Jan (after reconnect, started the 5 start countdown)

Typical commute is 20 minutes.
With morning temps sub-zero for most of past week, remote start runs for about 5 minutes before I get in.

Prior to replacing the aux, no lights. Just that I noticed it wasn't turning off at stoplights.

 

[sharpsicle]

I’ll just say that if you want to use ESS (which it sounds like you do), do NOT do the aux battery delete. This introduces a voltage drop risk that the aux battery is designed to mitigate.

 

[Lost1wing]

If you have accidentally shorted one of your cables during the main or Aux battery swaps, you could end up with the faults you are having. If the Jeep is failing the power up test, it is not liking one of your batteries. You need to check the fuse array. It is possible that you inadvertently blew one of the fuse array fuses. I would isolate the negatives at the main and measure the battery voltages while isolated. I would also check each part of the fuse array. If you check the battery voltages andcone is low, I would suspect the alternator is not charging it or that battery is bad.

 

[Sixt7gt350]

I’ll just say that if you want to use ESS (which it sounds like you do), do NOT do the aux battery delete. This introduces a voltage drop risk that the aux battery is designed to mitigate.

I definitely do NOT like ESS, would frequently press the button to disable after it turned off at a light, just didn't always remember to do after a start.

When it didn't turn off, even though I hadn't yet pressed the button, was how I first noticed it might be time for a new aux. (No warning lights, just didn't turn off like it normally would)

 

[Sixt7gt350]

If you have accidentally shorted one of your cables during the main or Aux battery swaps, you could end up with the faults you are having. If the Jeep is failing the power up test, it is not liking one of your batteries. You need to check the fuse array. It is possible that you inadvertently blew one of the fuse array fuses. I would isolate the negatives at the main and measure the battery voltages while isolated. I would also check each part of the fuse array. If you check the battery voltages andcone is low, I would suspect the alternator is not charging it or that battery is bad.

Getting ready to go out to check individual voltages and check fuses.
Other than F42, which fuses are related to this abominable ESS system?

 

[Andy29847]

Sorry you are having such a struggle. You are not the first one to have this experience. That is one of the reasons I think the design of the Jeep stop/start/battery system is poor. I shared this link in my first post on this thread. The title of the post starts with "Peace of Mind at Last."

https://www.jeepgladiatorforum.com/...ery-with-a-premium-h7-group-94-battery.76866/

 

[sharpsicle]

I definitely do NOT like ESS, would frequently press the button to disable after it turned off at a light, just didn't always remember to do after a start.

When it didn't turn off, even though I hadn't yet pressed the button, was how I first noticed it might be time for a new aux. (No warning lights, just didn't turn off like it normally would)

Fair enough.

If you’re going to delete the aux battery, I would then highly recommend some sort of auto start/stop eliminator. The last thing you want is forgetting to hit the button and it to start engaging ESS without the second battery. That leads to problems.

 

[Andy29847]

Fair enough.

If you’re going to delete the aux battery, I would then highly recommend some sort of auto start/stop eliminator. The last thing you want is forgetting to hit the button and it to start engaging ESS without the second battery. That leads to problems.

I have never read of someone having problems caused by stop/start after switching to one battery.

https://www.jlwranglerforums.com/fo...e-after-switching-to-just-one-battery.140959/

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