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Help. Time sensitive! Calling Jeep Gladiator Battery Experts. Need help and I'm in Peru.

HourlessLife

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Hey everyone. So I'm trying to drive around the world with my family. We're currently in Lima, Peru.

Like an idiot I forgot to disconnect my battery when we flew back to the states to visit family for 3 months for the holidays.

When I came back, my main cranking battery was dead. I suspect that auxiliary battery is dead too.

Here's where I need your help. I have limited access to internet here. So I need some specific answers to questions that will help me get this resolved for my family. I appreciate anyone taking the time to respond to my questions.

My Jeep is a 2021 Jeep Gladiator Sport S with Max Tow Package. (It has a larger battery I believe)

I need to know the answers to the following questions:

1. What specifically is the OEM battery that comes with the Max Tow package on the 2021 JT. I need the numbers off the thing so I can see if I can track one down here in LIma.

2. Same with the Aux batter. What specifically is the OEM aux battery that comes with the Max Tow package on the 2021 JT. Again. I need the numbers.

3. Has anyone replaced the aux battery by going through the passenger side wheel well? I read somewhere on a Jeep forum that it was easier than taking off the fuse box. I have limited tools here, and it is freaking hot.



I was able to jump start the rig, and when I tested it had 12.5v on the cranking battery. But this morning it was down to 3.5v and the inside of my rig looks like a discotheque. The PRNDL is flashing, my overhead lights are flashing, and the Jeep just isn't happy.

Hoping for some help. I'll log back in and check when I have better internet.

Thanks in advance.

Eric
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kevman65

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Large main battery is 94R or H7, same battery two categories.

Auxiliary battery is Group size 400 or AUX14.

Part numbers won't help you, so many have been discontinued and changed, plus different parts of the world get different batteries per my search. As in North America and South America have different batteries.
 

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In addition to what @kevman65 said about the battery sizes, they ideally need to be AGM and not flooded lead acid batteries that is probably what you are going to find down there more often than not. I would only put in a flooded lead acid battery only as a last resort to drive somewhere to get a AGM.

Wish you luck.
 

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Free2roam

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I'd probably go battery delete for the aux battery. Then just get the 94R. No more six battery to deal with or Genesis dual set up.
 
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HourlessLife

HourlessLife

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Update:

My biological father wasn’t present when I was a kid. My mother knew nothing of mechanics. So I grew up devoid of any mechanical instruction whatsoever. Not the best trait in someone who is trying to drive around the world.

So expect me to come to y'all again asking for your combined wisdom.

When we left Lima, I forgot to disconnect the cranking battery. Silly 3 second mistake. But it cost me.

Thanks to everyone, I got after it.

So as y'all know, removing the cranking battery is easy. Got that done.

For the Auxiliary Battery, rather than go through the top and having to remove the fuse box and all that, I followed my friend's advice who had been through this and went underneath the passenger side front liner. SUPER EASY to access the battery. 10mm socket and long extension made the job pretty straight forward.

Just remove the screw (with 10mm bolt head) on the rear of the front passenger side fender liner and then peel back the liner. You don't have to remove any clips at all. If you lay down under the rig, you have perfect view of the bottom of the aux battery holder that has 3 10mm bolts you need to remove.

Magnetic flashlight recommended as well as safety goggles if you wheel at all. Stuff was falling all over my face. Take those three bolts out and the holder is removed. Grab the battery and disconnect the terminals. (Also 10mm)

My next step is to take these batteries to a large automotive battery shop about an hour away from where I am and get two new ones, bring them back and install them and then test everything.

I’m wiped.

The next step is to take both batteries to a large battery shop here in Lima and purchase replacements. I think I’m going to try and tackle that tomorrow.

Thanks again for all the assistance.

Eric
 

punk'n

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Not the end of the world, but you might want to try to top off the new batteries before the install.

A small compatible charger or tender overnight will do. Make sure it can charge AGM batteries if that is what you purchase.
 

ShadowsPapa

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Not the end of the world, but you might want to try to top off the new batteries before the install.

A small compatible charger or tender overnight will do. Make sure it can charge AGM batteries if that is what you purchase.
You DO want to charge them first. They won't be fully charged off the shelf. ALWAYS charge new batteries and reset the ibs.
 

punk'n

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You DO want to charge them first. They won't be fully charged off the shelf. ALWAYS charge new batteries and reset the ibs.
I know that.

I was trying to be gentle since he is in another country with probably not the best of support. Didn't want to rain on his parade if HE CAN'T pre-charge them.
 

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ShadowsPapa

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I know that.

I was trying to be gentle since he is in another country with probably not the best of support. Didn't want to rain on his parade if HE CAN'T pre-charge them.
His best bet in that case is to as soon as is possible, charge each independently, and reset the IBS.

Otherwise, there's a risk of under or over-charging.

Another possibility is to have the battery vendor/shop charge the batteries - at least as much as possible. Maybe call ahead and have them set out the batteries - even for 30-40 minutes would be a big help.
 
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ShadowsPapa

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This might be a good reference for the fender procedure to replace the aux:

https://www.jeepgladiatorforum.com/forum/threads/auxiliary-battery-swap.57725/

(I haven't done this myself. Any better write-ups?)

In your situation I definitely would use the fender procedure, so as not to risk any electronics damage going down under the fusebox
As has been proven - one can do it through the wheel opening without completely ripping things apart. It can be done by just pulling the rear of the liner out of the way.

Just hope he pulls the two negative cables apart from each other and makes sure they can't possibly touch ground during this process- maybe wrap 'em in rags, to prevent blowing the N3 fuse! You can bet he'd have trouble getting that part............
 

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Don’t fret if you can’t top the new batteries off, just let the truck run for 30 mins or so. (signed-the guy whose never done that ??)

IBS should be reset by the nature that you’ve had both batteries out but if you wanna be extra sure you can unplug it prior to reconnecting the batteries and plug it back in once they’re hooked up.
 

ShadowsPapa

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Don’t fret if you can’t top the new batteries off, just let the truck run for 30 mins or so. (signed-the guy whose never done that ??)

IBS should be reset by the nature that you’ve had both batteries out but if you wanna be extra sure you can unplug it prior to reconnecting the batteries and plug it back in once they’re hooked up.
Problem is - you need to match a "reset IBS" to a fully charged battery. It's going to assume it's that way.
Yeah, you can do whatever you want, but............ will it work properly and have the best battery life, the charging system operating as it should? Or, will it get by?

IBS won't be reset unless it's disconnected for long enough - some people pull cables off, swap out battery, put IBS back on and it was never disconnected for long enough.
I can easily swap out the crank battery - and not reset the IBS.

QUOTE from FCA STAR document -
Jeep Gladiator Help. Time sensitive! Calling Jeep Gladiator Battery Experts. Need help and I'm in Peru. 1704927658888

it be should installed onto a fully charged battery and follow the same learn procedure above.
 
 







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