ESS not working

[ShadowsPapa]

The IBS should be reset if batteries are replaced - by disconnecting and letting it sit disconnected for a bit.
If the IBS DOES need to be replaced due to a code, then it should be installed on fully charged batteries.
The state of the IBS and batteries should match. Otherwise the IBS will say one thing to the BCM but the state of the battery will be different than what it says.

If your dealer's techs aren't aware of this - they needn't be working with batteries or electric systems.

Service writers are often, well, not the best people to be advising what is needed or not needed.

Remember, it was service writers who told me that ABS doesn't work under 35 mph, and that my winch was draining my batteries.

There are great ones - like the fellow who helped me diagnose an HVAC and temp sensor issue - and didn't charge me. And another today cut a bill on half for me (and I never asked for that)

Sponsored

 

[ShadowsPapa]

My second time into the dealer for batteries they also replaced the IBS. I think they said it weren't able to tighten the terminal properly..

Sure, mechanical or physical failure can sure happen. They are man-made devices. I can see that - perhaps a stripped stud or other problem.
But too often, it's just "let's try replacing some stuff and see what happens".

 

[bd100]

... require battery charger ... be connected only onto the IBS module (B-) Negative battery post.
Connecting the battery charger onto the (B-) battery post creates "blind charging".
"DO NOT BLIND CHARGE".

I think I know what they mean, but the above contradictory text sure don't make it clear!

 

[Dan in Pasadena]

So I just got back from picking up my truck from the dealer. NO CHARGE!!

Shocking! Never thought that would be the case. They said the batteries were discharged, charged them up, test drove it and all is well. I'm suspicious because I drive the truck everyday. There would be no reason for the batteries to be discharged. I do NOT turn off the ESS, if anyone questions that.

Honestly, I expect the issue to surface again relatively soon. Also while there they updated the software for some kind of misfire issue? Anyway, DMV would not let me renew my yearly registration without the certificate that comes with the update so I've got it now.

 

[Mr._Bill]

So I just got back from picking up my truck from the dealer. NO CHARGE!!

Shocking! Never thought that would be the case. They said the batteries were discharged, charged them up, test drove it and all is well. I'm suspicious because I drive the truck everyday. There would be no reason for the batteries to be discharged. I do NOT turn off the ESS, if anyone questions that.

Honestly, I expect the issue to surface again relatively soon. Also while there they updated the software for some kind of misfire issue? Anyway, DMV would not let me renew my yearly registration without the certificate that comes with the update so I've got it now.

You drive it everyday, but how much is it driven? Long trips are necessary to keep the batteries charged, and will also cover up the issue of batteries that are slowly failing from age. Short trips will bring the issue up sooner, since the batteries don't get properly charged.

Plan on replacing both batteries soon. Fully charging them is a temporary fix. It means they are just healthy enough to not fail the Mopar battery test required for the dealer to be able to label them as bad.

 

[Dan in Pasadena]

You drive it everyday, but how much is it driven?

Around town running errands, etc. So not typically long drives. Before it threw the code I'd learned to feather the brakes and the ESS wouldn't happen.

Long trips are necessary to keep the batteries charged, and will also cover up the issue of batteries that are slowly failing from age.

Interesting that for literally a couple months I was getting the message that the battery was not ready or was charging - whatever the typical message says.

Then I drove it about 500 miles to my son's place and back and it wasn't til after that the computer (I guess) realized it wasn't "taking" the charge and threw the "@" light.

Plan on replacing both batteries soon. Fully charging them is a temporary fix. It means they are just healthy enough to not fail the Mopar battery test required for the dealer to be able to label them as bad.

The truck is a 2020 with 40,000 miles and it's factory batteries. If it throws the code again I won't bother with the dealer.

When it happens if I just replace both batteries myself what is needed to clear the code or will it clear on it's own when the computer senses full charges? Any particular recommendation on battery brand or size?

 

[Mr._Bill]

Around town running errands, etc. So not typically long drives. Before it threw the code I'd learned to feather the brakes and the ESS wouldn't happen.



Interesting that for literally a couple months I was getting the message that the battery was not ready or was charging - whatever the typical message says.

Then I drove it about 500 miles to my son's place and back and it wasn't til after that the computer (I guess) realized it wasn't "taking" the charge and threw the "@" light.



The truck is a 2020 with 40,000 miles and it's factory batteries. If it throws the code again I won't bother with the dealer.

When it happens if I just replace both batteries myself what is needed to clear the code or will it clear on it's own when the computer senses full charges? Any particular recommendation on battery brand or size?

The codes should clear on their own after the batteries are replaced. The largest size the battery tray will accommodate is a 94R. I put in a ACDelco 94R AGM battery that I managed to get from Amazon for $150 last September. Usually, Costco or Sam's Club have the best pricing on batteries. The Aux battery I ordered from Auto Barn. They are Deka batteries, around $120, and they usually have $10 off and free shipping promotions.

Just make sure that both batteries are fully charged before installation, and be careful with the battery cables so they don't short or contact any metal in the engine bay. If they do, it can blow the high current fuse, which is about $175 to replace. I would disconnect the main battery and secure the cables out of the way. Replace the Aux battery while being careful with the cables. You should be able to remove the five or six push pins and the two bolts and bend the fender liner back just far enough to reach the Aux battery to replace it. After that, replace and connect the main battery. It is normal to have some sparking when connecting the main battery cables. If you have the 8.4 Uconnect head unit, it will take up to 24 hours for it to return to normal operation.

I would also look at getting a battery maintainer, if it is going to sit for any length of time. The alarm, computers, and head unit all have a constant parasitic draw.

 

[Dan in Pasadena]

Thanks for the advice. The truck never sits undriven for even a day.

 

[SargeDiesel]

Thanks for the advice. The truck never sits undriven for even a day.

Another thread on this?
Do a search and you will find more than you can read.

 

[Mr._Bill]

Another thread on this?
Do a search and you will find more than you can read.

I would guess he did search, since he added to an existing thread instead of starting a new one. Some of these get way out in the weeds.

 

[SargeDiesel]

I would guess he did search, since he added to an existing thread instead of starting a new one. Some of these get way out in the weeds.

Didn't mean anything negative... just there is so much out there about the ESS... threads that are many multiple pages, not just two.
The same question has been answered probably 100 times or more... I only say this because it's been discussed so much, kinda like "the last jeep I'll ever own" thread. It wasn't meant to disrespect anyone, or atleast that wasn't my intention.

 

[Dan in Pasadena]

I DID search. That's why I renewed this one.

 

[ShadowsPapa]

I think I know what they mean, but the above contradictory text sure don't make it clear!

And worse - the pictures in their IBS training info aren't all that great, either.

Here's mine - green circle = OK
Not on the battery post or the IBS clamp - red X = not OK

Body ground is a great place to connect if you can get to it.
Or like the Grand Cherokee has - jump starting posts on the right fender inside the engine bay.

 

[XraytecH]

Have your dealer replace both batteries.

 

[Andy29847]

This is what I suggest.

Remove the aux battery negative cable, insulate the end, and tie it back out of the way.

Pull fuse f42 to disconnect the power control relay.

Buy and install a H7/group 94 EverStart battery from Walmart.

Your truck will function the same on one battery as it does on 2. Better yet, having just one battery takes all the mystery out of what to do if your start getting "messages" from your Jeep.

Sponsored