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3.6L Aux Battery Options

ResqFE

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Is there a upgraded or better performing aux battery for the 3.6L? I seem to get about 2.5 years since the last replacement. Sucks....

Any help or suggestions appteciated. Thanks
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Rhinebeck01

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Is there a upgraded or better performing aux battery for the 3.6L? I seem to get about 2.5 years since the last replacement. Sucks....

Any help or suggestions appreciated. Thanks
I do think bypassing the Aux battery is a better way to go then keeping an Aux in the mix.
Takes less then 5 min. to bypass the Aux battery.

For Aux replacement.. The best that I know of is this Braille that is known to fit the JL, Aux battery box, has proper connect points and lots of CCA compared to all the other Aux's out there.

Braille (Part# B14115) I5Ah 360CCA
Tests from factory at 483 Crank Amps. Wt. 11.5 lbs.
 

Fudster

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Is there a upgraded or better performing aux battery for the 3.6L? I seem to get about 2.5 years since the last replacement. Sucks....

Any help or suggestions appteciated. Thanks
Hey Ron:

I don't mean to contradict @Rhinebeck01's thoughts above. In fact I'd agree that if an owner takes steps to see that ESS not (or doesn't want ESS to) engage, that removal of the Aux battery from the vehicle's electric schematic, if not physical removal as well, makes sense. And certainly, if committed to the minimal size requirements of the stock ESS battery, his suggested aftermarket substitute for it appears to provide more ability for equal size than that Stellantis provides.

Assuming that your committed to the two battery approach there are a few other things that come to mind. The first, if you have access to shore power while parked, is that you trickle charge your rig while at rest. Attaching such a device's connectors to the main battery will charge both batteries, as the two batteries are connected in parallel at all times but an instant at crank and during ESS events.

Another charging option, although by no as inexpensive, but perhaps the only one if shore power isn't available to you is something like the Cascadia hood solar charger. https://www.cascadia4x4.com/products/jeep-wrangler-jk-vss-system-hood-solar-panel If you do go this route make sure to get the one that is compatible with your JL's hood.

(Owner's who park in enclosed (public) garages best not take this route.)

Another also expensive, perhaps even overkill or even less than perfectly equipped solution is the acquisition of the Genesis Offroad dual battery kit. https://www.genesisoffroad.com/jeep-dual-battery-kits. In its use of two equally sized identical chemistry batteries I believe that some of the potential for the ESS stock battery to canabolize the main battery is absent. But this solution is more for the offroader seeking to control appliance draw than merely a frustrated ESS battery owner. In fact the kit will limit you to 6 ESS events per cold crank (more on why available on request.)

A slightly cheaper option is to get the batteries and tray from Genesis without the intelligent components that interface them..simply making one of the batteries your main, and the other your ESS battery.
 
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ResqFE

ResqFE

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My primary battery has been on a charge since last night, went from 19% to 67%. Not seeing it holding a charge and will be replacing it with a better than OEM battery.
That being said, can I remove the aux battery and simply pull the F42 fuse?
 

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My primary battery has been on a charge since last night, went from 19% to 67%. Not seeing it holding a charge and will be replacing it with a better than OEM battery.
That being said, can I remove the aux battery and simply pull the F42 fuse?
I have no idea what @Rhinebeck01 finds funny about my post.

Jeep Wrangler JL 3.6L Aux Battery Options 1666986422746


For others I'd chalk it up to a mis-pressed icon reaction but in his case/history I'd guess it vacant derision.

Please don't hold your breath waiting for his explanation (although maybe another mocking icon, which in absence of explanation I think should be ignored.)

There won't be one, because all I said was on point; me being the first to cite expense and overkill with some of my suggestions, but I put them out there for readers as options. To point, for those with ESS battery issues and need to run overlanding appliances Genesis is an great, albeit expensive solution.

As to trickle charging, @Rhinebeck01 can't possibly be opposing an avenue he advocates and points out here that he does on occasion himself. And while Cascadia solutions are orders of magnitude more expensive than a trickle charger, some of us park, as mentioned, where we don't have access to shore power.

To be clear, trickle charging I believe will help maximize battery life, as you requested suggestions on, but I know won't bring back a shot battery back to life.

~~~~

Anyway, more important, to your question: "can I remove the aux battery and simply pull the F42 fuse?"

Yes. But you can simply, if you prefer, and at least initially, disconnect the black cable from the Aux battery to the main battery's negative post without going through the effort of physically yanking the ESS battery right now.

Two black factory cables lead to the main battery's negative post. One has as its other end the body ground on the passenger's side front quarter panel. Leave that cable untouched and attached to the main battery's negative post. It is the other cable you remove from the main battery's negative post and ideally wrap its end in electric tape.
 
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My primary battery has been on a charge since last night, went from 19% to 67%. Not seeing it holding a charge and will be replacing it with a better than OEM battery.
That being said, can I remove the aux battery and simply pull the F42 fuse?
That's why I did recently and couldn't be happier. That aux battery is nothing but trouble until you use it as a backup starter battery :like:.

I tried... I gave that system so many chances until it almost ruined my brand new and expensive odyssey.

I am part of the aux bypass club now.
 
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ResqFE

ResqFE

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Did the bypass mod today as well.... we will see how this goes.
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