Battery Protection Mode - I Guess It's My Turn...

[CarbonSteel]

My JL has about 45K on it and it will be 3 years old in August. Recently, I took an emergency trip to Texas and my Jeep was parked at Denver airport for about 4 days and the temperatures were subzero Fahrenheit for most of that time. When I returned, it was -8°F and it turned over slowly but started.

Since then, ESS has not worked, and I am either in battery protection mode or battery charging mode. I am guessing that either the auxiliary battery or the main or both need to be replaced. If one or the other is toast I am replacing both.

What say you? Aux battery on its last legs?

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[Rhinebeck01]

My JL has about 45K on it and it will be 3 years old in August. Recently, I took an emergency trip to Texas and my Jeep was parked at Denver airport for about 4 days and the temperatures were subzero Fahrenheit for most of that time. When I returned, it was -8°F and it turned over slowly but started.

Since then, ESS has not worked, and I am either in battery protection mode or battery charging mode. I am guessing that either the auxiliary battery or the main or both need to be replaced. If one or the other is toast I am replacing both.

What say you? Aux battery on its last legs?

@CarbonSteel

Don't even think about replacing just the Aux. Acquire both the Main and the Aux and do the deed... Or jumper out the Aux and replace just the Main.

 

[CarbonSteel]

@CarbonSteel

Don't even think about replacing just the Aux. Acquire both the Main and the Aux and do the deed... Or jumper out the Aux and replace just the Main.

Nope; that's why I said if I one or the other is toast, I'm replacing both.

Will probably go with these:

Main = https://shop.advanceautoparts.com/p...6-P?navigationPath=L1*14920|L2*15000|L3*15597

Aux = https://shop.advanceautoparts.com/p...8-P?navigationPath=L1*14920|L2*15000|L3*15597

 

[kieseki]

If you have access to a smart charger and a battery load tester, you can try to charge and test both batteries before spending money and going through the effort of swapping batteries.

Just make sure you isolate the main and aux for both the charging and load testing, otherwise the readings will not be accurate. If either batteries don’t hold charge or fails the load test, then it’s time to replace both.

 

[CarbonSteel]

I replaced the main battery today and will replace the AUX when it arrives later this week. Pretty straightforward swap. I did take the time to separate the negative cables and tape the ends just to make double damned sure I did not have a short when messing with the positive cables that would have created a mess with blown fuses.

Although I had an H7 battery from the factory, it appears the Diehard replacement has more CCA than the OEM. Not sure if they are measured in the same way, but if so I'll take those extra amps--especially when the temperatures drop below zero here in CO.

 

[mwilk012]

I replaced the main battery today and will replace the AUX when it arrives later this week. Pretty straightforward swap. I did take the time to separate the negative cables and tape the ends just to make double damned sure I did not have a short when messing with the positive cables that would have created a mess with blown fuses.

Although I had an H7 battery from the factory, it appears the Diehard replacement has more CCA than the OEM. Not sure if they are measured in the same way, but if so I'll take those extra amps--especially when the temperatures drop below zero here in CO.

The group size measurements are a physical dimension, not necessarily a rating. In fact, every major brand I’ve seen list higher CCA than factory.

 

[WranglerMan]

I doubt this may help many since I’m not running stock batteries but I have been running a dual Genesis system with twin Full River 750’s and have ESS disabled using a Smart Stop/Start module and until about a month or so ago I never had any issues but I do occasionally test ESS as I use this as a sort of tool along with JSCAN to read any codes.

Long story story like I said all was going good but recently I to started to get the “Battery Protection Mode” message and have never had issues with starting issues and have had my batteries load tested several times and they both passed.

If you are familiar with how the JL charges and have followed Jerry’s studies there are several ways to figure out what’s going on and in my case the IBS is connected to my aux battery and there is a solenoid and smart relay that opens and closes so it was suggested that the opening and closing of this relay may be the cause as it gets possibly confused on how to correctly charge so some have moved the IBS to the main crank battery that are using the Genesis system but in my quest to test I chose to disable the IBS using JSCAN and low and behold my charging system appears to work as designed with the smart alternator doing its dance and my batteries have passed several loads tests and no more error messages and ESS during multiple tests has passed.

I know this may not help some but sometimes it helps to look at more than one thing as the root cause

 

[CarbonSteel]

Received the AUX battery today with a 03-2022 build date. While I expected that it would be small, this thing is much smaller than I expected. No wonder they do not last that long. I plan to install it when the temps stay above freezing for a day.

 

[CarbonSteel]

I wanted to post a bit of feedback since I have been running both batteries for a few weeks. The ESS system is back to normal and there are some things that I have noted (as likely would be expected with new batteries, but for what it is worth):

-- ESS has been performing flawlessly and by that, I mean that it works when it should AND it lasts a lot longer before the engine restarts. TBT after the first year or so, it would not last the entire stop light before restarting and it does that now quite easily.

-- The engine runs better (yeah, I know placebo), but it does not seem to be as "burdened" as it did before. Not sure if the alternator was putting extra load on the engine or not, but I like it.

-- The voltage was frequently in the 14.x volt range nearly all the time, but now it sometimes hits 13.x volt range and then hangs in the 12.4-12.7 range most of the time. Again, this is likely expected behavior, but wanted to share in case others were seeing what I was prior to changing the batteries.

 

[WranglerMan]

@CarbonSteel this is how my system operates ( same as yours ) even though I don’t run the stock setup, I had some issues with the battery protection mode but since disabling the IBS all has been 100% and I rarely see 14+ unless it’s been parked for a week and then the voltage drops to the mid 13’s after a good drive and continues to drop. I recently had my batteries tested again and all is good.

 

[CarbonSteel]

@CarbonSteel this is how my system operates ( same as yours ) even though I don’t run the stock setup, I had some issues with the battery protection mode but since disabling the IBS all has been 100% and I rarely see 14+ unless it’s been parked for a week and then the voltage drops to the mid 13’s after a good drive and continues to drop. I recently had my batteries tested again and all is good.

I have JSCAN and considered disabling IBS after seeing others do it, but I am not sure what it gains. Is it to stabilize the charging rates or?

 

[WranglerMan]

I have JSCAN and considered disabling IBS after seeing others do it, but I am not sure what it gains. Is it to stabilize the charging rates or?

Since I currently run the Genesis system my system seems to more stable on charging as now it does not monitor the aux battery it’s hooked up to and as Jerry and I have discussed with the way the relay opens and closes on my setup the IBS gets confused on charging.

Currently my factory ESS negative cable is gone and the ESS positive is hooked to the main crank battery and I still have the IBS connected but disabled thru JSCAN as when it’s unplugged it generates a code and dash error and I believe this is because I don’t have the TSB since mine is a 2018 as some that have that TSB applied just unplugged their IBS without a error code.

My voltage during a long drive just drops and drops and have be settling at 12.9-13 and after its been parked for 4-5 days the EVIC display is usually around 14 but drops to mid 13’s after a short drive and as I said the more I drive the lower it goes and of course when slowing or braking it ramps up to over 14 then drops back down and no errors or dash messages at all and I carry a scan tool in my console and every time I have checked for codes there are none.

 

[CarbonSteel]

Since I currently run the Genesis system my system seems to more stable on charging as now it does not monitor the aux battery it’s hooked up to and as Jerry and I have discussed with the way the relay opens and closes on my setup the IBS gets confused on charging.

Currently my factory ESS negative cable is gone and the ESS positive is hooked to the main crank battery and I still have the IBS connected but disabled thru JSCAN as when it’s unplugged it generates a code and dash error and I believe this is because I don’t have the TSB since mine is a 2018 as some that have that TSB applied just unplugged their IBS without a error code.

My voltage during a long drive just drops and drops and have be settling at 12.9-13 and after its been parked for 4-5 days the EVIC display is usually around 14 but drops to mid 13’s after a short drive and as I said the more I drive the lower it goes and of course when slowing or braking it ramps up to over 14 then drops back down and no errors or dash messages at all and I carry a scan tool in my console and every time I have checked for codes there are none.

Ah, ok. After replacing both batteries, mine is displaying the same behavior with the IBS enabled. However, as the AUX battery started to die, the voltage was almost always in the 14v range and I assume this was the alternator compensating for as well as attempting to charge a battery that would take or hold a good charge. As these new batteries age, I may be able to predict when the AUX is going again when I see the 14v behavior start to appear again. Not sure if that is foolproof, but it may be a good indicator.

I considered going to the Genesis system, but I have relays mounted and wiring tucked around the battery that would have to be relocated. The batteries lasted nearly 3 years and 45K miles, so I am OK with that. The main may have lasted a bit longer, but in -8°F weather, it would crank slower than it should so I opted to replace both at the same time.

 

[Valpo Jeep]

Sorry to dig up an older thread. I am having the protection mode issues currently.

I just went through the fuse box and seated everything so I shall see if that helps at all.

So yesterday I had to jump the Jeep off the jump pack and drove it around for a while and it seemed to be charging fine. Voltage readout on the dash screen was 14.6 V. Got home and put it on the charger for about 14 hours and read the battery at 13.8 V. Disconnected the charger and it proceeded to drop to around 12.6V over a few hours and held that. Went to the store and the dash was reading 13.7 V when running. Start / stop not available due to battery protection mode. Left the store an hour later, still in protection mode but now the dash was saying 12.7 V.

have to go out again soon but will be taking the jump pack with.

is this all the classic aux and main battery dying signs?

 

[CarbonSteel]

Sorry to dig up an older thread. I am having the protection mode issues currently.

I just went through the fuse box and seated everything so I shall see if that helps at all.

So yesterday I had to jump the Jeep off the jump pack and drove it around for a while and it seemed to be charging fine. Voltage readout on the dash screen was 14.6 V. Got home and put it on the charger for about 14 hours and read the battery at 13.8 V. Disconnected the charger and it proceeded to drop to around 12.6V over a few hours and held that. Went to the store and the dash was reading 13.7 V when running. Start / stop not available due to battery protection mode. Left the store an hour later, still in protection mode but now the dash was saying 12.7 V.

have to go out again soon but will be taking the jump pack with.

is this all the classic aux and main battery dying signs?

Sounds like the AUX battery is going and if it is, change them both, but go from the bottom (through the fender) to change the AUX instead of through the PDU.

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