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Jumperless Aux Battery Bypass

Ratbert

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Can I also change tire sizes, gear ratios, and disconnect in 2wd with the smart stop? Or is it just for stop start?
Apparently the SmartStopStart does that one thing very well. I'm fairly confident, however, that that's all it does. That's why I questioned some of the previous responses.

I'm also fairly confident that it doesn't disable ESS any better than the Tazer JL, but it's extremely likely to be easier to use and less likely to have unintended side effects. There also should be no need to remove it when taking your Jeep in to the dealership.

It's a trade-off.
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Erfrantz653

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I removed aux battery. Ran aux battery cables up to main battery and connected them, pulled f22 fuse, so far no errors, i was getting battery charging error for ess, now ess works correctly, i have a tazer so no problem disabling ess
 

grandsrus

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I removed aux battery. Ran aux battery cables up to main battery and connected them, pulled f22 fuse, so far no errors, i was getting battery charging error for ess, now ess works correctly, i have a tazer so no problem disabling ess
You meant F42 fuse?
 

Mtrctylarry

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I removed aux battery. Ran aux battery cables up to main battery and connected them, pulled f22 fuse, so far no errors, i was getting battery charging error for ess, now ess works correctly, i have a tazer so no problem disabling ess
Just saw your post or I would have replied sooner.... Glad you got it worked out.

I have been pretty busy.

In the last 3 days, I have changed out 3 Aux batteries and 3 Main batteries on other peoples JL's. I did manage to get one other guy to just have me do the jumper-less bypass on his JL.

Anyway, I'm sure you will soon be saying to yourself.... Why did I not do an Aux battery bypass sooner..
I am still using the aux. battery cable off and isolated, PCR removed. with jumper in place. In your opinion could I replace PCR and remove F42, remove the N1 -N2 jumper and have the same results of isolating aux. batt. and still use as reserve battery?
 

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Rhinebeck01

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I am still using the aux. battery cable off and isolated, PCR removed. with jumper in place. In your opinion could I replace PCR and remove F42, remove the N1 -N2 jumper and have the same results of isolating aux. batt. and still use as reserve battery?
@Mtrctylarry

Yes.....or just leave it the way you have it.
 

Mtrctylarry

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Rhinebeck01 - you seem to have done the most research.

If you pull F42 fuse. Tape off the aux wire. I like the idea of having a spare battery I can connect just in case I need it. I've noticed with my base sport there is no warning that I've left the lights on because I don't bother to reconnect the door wiring harness (manual locks, manual windows). So having a built in "jump start" battery seems a decent way to get value from the AUX.

How long will the aux hold a charge?
How often should I charge it?
I have a Noco Genius 1 trickle charger.
I also have a Schumacher 30/6 2 am charger Model SC1281.

This is my daily driver.

Hooking the AUX to a charger will be a bit of a pain if you tape off the lead to avoid a spark.
Would need to UNTAPE to get a connection.

Ideas, comments, thoughts?
I use a piece of vinyl tubing which isolates cable end and also allows me to slip on the clip from my charger...Deltran trickle charger. Usually charge aux. about once every couple of weeks, takes about an hour to reach full charge.

Jeep Wrangler JL Jumperless Aux Battery Bypass IMG_1888.JPG


Jeep Wrangler JL Jumperless Aux Battery Bypass IMG_1887.JPG


Jeep Wrangler JL Jumperless Aux Battery Bypass IMG_1889
 

Rhinebeck01

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I use a piece of vinyl tubing which isolates cable end and also allows me to slip on the clip from my charger...Deltran trickle charger. Usually charge aux. about once every couple of weeks, takes about an hour to reach full charge.

IMG_1888.JPG


IMG_1887.JPG


IMG_1889.jpg
@Mtrctylarry

I really like your vinyl tubing method... very clever! ........ another thing you can use is a 5" piece of
Wire Loom Split Tubing/Auto Wire Conduit Flexible Cover. (see pic below) You just slide it down over the disconnected cable connector and when you need the cable end you slide it off the cable connector end of the cable.

I hook up my bypassed Aux battery, to a 5 amp battery maintainer tender that is aok to use with AGM batteries, every 2-3 weeks.. I have been doing this for 3 or so yrs now and the original Aux that came with my JL in 2018 still passes load tests.

Jeep Wrangler JL Jumperless Aux Battery Bypass loom
 

entropy

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I use a piece of vinyl tubing which isolates cable end and also allows me to slip on the clip from my charger...Deltran trickle charger. Usually charge aux. about once every couple of weeks, takes about an hour to reach full charge.

IMG_1888.JPG


IMG_1887.JPG


IMG_1889.jpg
brilliantly simple. I am getting one for myself.
 

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Jammer

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That makes sense. Just remember if your still in warranty you may need to hook that aux back up if it has to go to the dealer. I know most of us don’t go to the dealership unless necessary but just a thought.
how can the dealer say it would void a warranty ? how can it make something go bad and break ?
 

Stuckinthesand

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how can the dealer say it would void a warranty ? how can it make something go bad and break ?
It would not void the warranty but they would most likely blame any ESS related issues on the fact the battery is disabled. That is why I recommend until warranty is expired to just tape off the negative and leave the battery in place.
 

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Just changed out my factory battery this morning and bypassed the auxiliary battery. Thank you very much for the information!
 

Pixels_JLU

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@Jebiruph Amazing amount of info in here and I thank
You and everyone else. Seems Aux batt killed main yesterday so had to get new one. Removed negative to Aux, installed new batt, removed 42. Started right up. Taser kept ESS button in off. But I have engine light on dash now. Is this common? Does it clear? No Obie to this part so please thanks for all info,

JP
 
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WhatExit?

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So many threads on ESS, jumpers, bypass, dual batteries, aux battery, etc. and so much good info thanks to @Jebiruph and many others.

Simple question ? what’s the best option for those of us running the factory 2-battery setup to ensure reliability especially when offroading (overlanding)?

I hoped the synopsis thread would be the answer, but that threads going on for many pages and now with this new fuse removal option, I’m just confused as ever. Thanks for your help.
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