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Aux Battery Delete - Need Help!

Centurion07

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Ok. This is different from what I gleaned from your prior reply.

It sound like you have taken the cables that were connected to the Aux battery and put them on the main battery's co
Just the positive. Taped the ground (that was connected to the aux). Threw the aux battery away.
 

rossneill

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The day has finally come: my battery died after less than 2 years of ownership. Now, I’m fully aware of the aux battery (AKA the parasitic battery) issue, and have researched the topic thoroughly, but I still have a few questions.

The way I see it I have a few options: replace the aux battery. Aux battery delete by removing battery, taping the wires, and pulling fuse 42. Buy a tazer/mini and turn off ESS. Buy an ESS bypass cable.

Questions:
If I delete the aux battery, do I have to feed the aux ground up to the main battery and connect it? Which cables do I need to tape and which do I need to connect to the main battery? Keep in mind I have a MY23, and I’ve seen conflicting reports that my MY has different cables.
If I buy a tazer/mini/ESS bypass cable, do I still have to replace the aux battery? Will the parasitic battery drain the main battery with these tools on?

Appreciate any insight into my questions. I’m trying to figure out the best option before I start down this path. I have upgraded the main battery with an H7 and I don’t want the parasitic battery to deplete the new battery in any way.
This is what I did.......
if your under 36000 miles have dealer replace battery under warranty
 

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jludave

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if your under 36000 miles have dealer replace battery under warranty
Feasible, but pushes the issue down the road. Eventually one will have issues with the aux, which will in turn kill the newer main. It is still best to bypass the aux, even if the main is replaced under warranty.
 

Centurion07

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Feasible, but pushes the issue down the road. Eventually one will have issues with the aux, which will in turn kill the newer main. It is still best to bypass the aux, even if the main is replaced under warranty.
OP doesn't have an aux. This thread is a little squirrely.

But for those who do have an aux, I wholeheartedly concur.
 

TopWright

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The day has finally come: my battery died after less than 2 years of ownership. Now, I’m fully aware of the aux battery (AKA the parasitic battery) issue, and have researched the topic thoroughly, but I still have a few questions.

The way I see it I have a few options: replace the aux battery. Aux battery delete by removing battery, taping the wires, and pulling fuse 42. Buy a tazer/mini and turn off ESS. Buy an ESS bypass cable.

Questions:
If I delete the aux battery, do I have to feed the aux ground up to the main battery and connect it? Which cables do I need to tape and which do I need to connect to the main battery? Keep in mind I have a MY23, and I’ve seen conflicting reports that my MY has different cables.
If I buy a tazer/mini/ESS bypass cable, do I still have to replace the aux battery? Will the parasitic battery drain the main battery with these tools on?

Appreciate any insight into my questions. I’m trying to figure out the best option before I start down this path. I have upgraded the main battery with an H7 and I don’t want the parasitic battery to deplete the new battery in any way.
I have a 2019 JLUR. I removed the aux battery and moved the positive aux cable up and connected to main battery post. Wrapped the ground cable and left in the aux box just so I didnt hear it rattling/bouncing around. Everything works as if the Aux was still there. I have the tow pkg and a H7 battery.
 

AdamHI

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I had same problem today on my 2020 3.6 Rubi. I watched a few vids. Disconnected main battery cables. Pulled the 42 fuse and reconnected cables. Jeep cranked right up. Had 2 warning lights on and rear backup cam didn't work. About an hour later everything corrected itself and everything works. Question I have... Is it really necessary to disconnect the negative cable off main to the aux battery? What's the downside of just leaving it connected?? Thx.​
 

jludave

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Is it really necessary to disconnect the negative cable off main to the aux battery?
Yes.

What's the downside of just leaving it connected?
The aux battery is connected in line with the main battery. If the aux battery is still connected and it goes bad, it will take the main with it (and vice versa). Disconnecting the aux battery, takes it out of the picture completely.
 

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AndySpill

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Yes.



The aux battery is connected in line with the main battery. If the aux battery is still connected and it goes bad, it will take the main with it (and vice versa). Disconnecting the aux battery, takes it out of the picture completely.
Dave is spot on. I just want to add some color commentary @AdamHI.

Dave is describing a parallel connection between batteries (positive terminal connected to positive terminal, negative to negative.)

With parallel connections, which should occur between batteries of similar chemistry (as is the case here, both are Absorbent Glass Mat or AGM batteries: a type of Lead Acid battery) and voltage, current will flow from the battery with weaker voltage to the one with more until that voltage is equal: no different than connected two glasses of water of different heights at their bottom and watching the water come to the same height in each.

The problem is if one of those batteries in parallel is defective it can suck current out of the good battery but not absorb it in kind.
 

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Any potential problems with just leaving a bypassed aux battery sitting in the Jeep forever?
 

jludave

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Voodooridr

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Is there a write up with step by step instructions and pictures for this aux battery bypass? the battery in our 2020 (2.0T) is most likely the original and we'd like to swap it out before another north Idaho winter kills it and since we have an ESS bypass I'd like to get rid of that little electrical jem
 

jludave

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Is there a write up with step by step instructions and pictures for this aux battery bypass?
Remove fuse F42. Then disconnect aux battery negative and isolate. It should be the thinnest of the negative cables on the 2020.

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