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Auxiliary Battery Swap

exfil offroad

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If anyone is having issues with their Auxiliary Battery and looking to replace it, I put together this quick video that shows you how to do it without removing your engine bay fuse box. Hope this helps.
Replacing your Jeep Auxiliary Battery
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ShadowsPapa

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That's the way the shops do it, the normal method to access it, through the fender liner.
It's probably in the flat rate "procedure book" or other resource.
When the dealership checked mine, they even documented what they pulled to get to the battery on the paperwork.

Just a word of warning to folks - if you pull the negative and positive cables off the main or crank battery, make bloody well sure that positive cable doesn't touch ground as it's hot just sitting there as it goes to the aux positive terminal electrically. In other words, if you let that positive cable hit ground once you pull it off the crank battery, you may blow a fuse.
(EDIT: - or the truck may blow a fuse, and then you blow a fuse because you blew it)
 
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PlayfulBird

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Is there a way to actually read out the quality(test the battery), or charge/recondition just the aux battery with out removing fender well or the TIPM (thats what its called right?)
I know they in some states are switched together and in others are isolated? Sorry, I don't really understand what Jeep did there
 

ShadowsPapa

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Is there a way to actually read out the quality(test the battery), or charge/recondition just the aux battery with out removing fender well or the TIPM (thats what its called right?)
I know they in some states are switched together and in others are isolated? Sorry, I don't really understand what Jeep did there
While sitting, not running, engine shut off, they are together.

You could connect battery charger POS to N1 terminal on the drivers side end of the PDC/fuse panel, pull fuse N3 and hook the charger NEG to the top of the crank battery negative.
You could pull negative cables off the main battery and connect the charger + to the N1 terminal and to the negative cables removed from the crank battery, a couple of ways to do it.
It would seem that connected + to N1 and pulling N3 fuse would be about the least intrusive, IMO.

Maybe someone has a better, easier idea.
 

PlayfulBird

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While sitting, not running, engine shut off, they are together.

You could connect battery charger POS to N1 terminal on the drivers side end of the PDC/fuse panel, pull fuse N3 and hook the charger NEG to the top of the crank battery negative.
You could pull negative cables off the main battery and connect the charger + to the N1 terminal and to the negative cables removed from the crank battery, a couple of ways to do it.
It would seem that connected + to N1 and pulling N3 fuse would be about the least intrusive, IMO.

Maybe someone has a better, easier idea.
Ha, thats already a great idea. The guys here at the battery place looked at me like I was insane when I told them I had an aux battery, and no it is not under the passanger seat but under all that stuff. They shrugged and packed up their tester and told me they had no idea how to check it and were not going to dig in there.
 

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I replaced mine through the top, and I wouldn't do it any other way after watching that video.
 
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exfil offroad

exfil offroad

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That's the way the shops do it, the normal method to access it, through the fender liner.
It's probably in the flat rate "procedure book" or other resource.
When the dealership checked mine, they even documented what they pulled to get to the battery on the paperwork.

Just a word of warning to folks - if you pull the negative and positive cables off the main or crank battery, make bloody well sure that positive cable doesn't touch ground as it's hot just sitting there as it goes to the aux positive terminal electrically. In other words, if you let that positive cable hit ground once you pull it off the crank battery, you may blow a fuse.
thats new, when they replaced mine a couple years ago they didnt tell me crap.
 
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exfil offroad

exfil offroad

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Is there a way to actually read out the quality(test the battery), or charge/recondition just the aux battery with out removing fender well or the TIPM (thats what its called right?)
I know they in some states are switched together and in others are isolated? Sorry, I don't really understand what Jeep did there
not that im aware of.
 

OVERLORD

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I think my Aux battery is starting to go, thanks for the video!
 

ShadowsPapa

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not that im aware of.
There absolutely is. I've shown how you can charge the aux battery alone and pull only negative cables off the ibs.
Charger on pos post of main battery and the negative cables you took off the ibs on the main battery. That charges only aux battery.
 

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I think my Aux battery is starting to go, thanks for the video!
In my opinion, it's easier to remove the full fender than to remove the liner as shown in the video. The fender rivets can be a pain to replace. There are numerous videos that show pulling the liner, but I have not yet seen one showing how to replace the fender rivets. To remove the fender, just remove 4 bolts that hold the fender to the braces, start to pull the fender to disengage the fender enough to access the plug for the fender lighting, then continue pulling the fender off. I did it in less than 5 minutes (most of which was spent trying to unplug the darn lighting plug). You might want to grab some of the fender clips from a parts store in case you break any. I broke one but had picked some up from Napa. The fender re-installs faster than the time it took to remove it. I had plenty of room to replace the aux battery without even removing the tire/wheel (35s with Mopar lift).
 

OVERLORD

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Out of factory warrantee.

Getting a message, "Aux switches out, Battery charging".

Load tested main battery, tested good.

Must I remove the terminals off of the main battery to change only the Aux battery?

Gonna go through the fender.

Thanks folk, been reading too much about this, I'm all twisted now.
 

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So who's making a replacement fender liner with a quick access section to get to the AUX battery, or a quick access add-on that can be installed after cutting out a hole from a template?
 
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Mr._Bill

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The fender liner is supposed to be flexible enough that the bolts and pins underneath can be removed, and it can be peeled back far enough to change the battery without removing the liner or the fender. Of course, warmer weather will make it more flexible. I still have to change my Aux battery, and that is what I plan to try.
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