Jumperless Aux Battery Bypass

[Stuckinthesand]

Thanks for pushing though on this. Oddly, my aux negative disconnect and main battery ground seem to be the opposite of what's shown in the videos in the other ESS disable post. Thinking I might have missed a twist in the pairing without pulling everything out, I followed the instructions anyway for pulling that lead off after pulling the fuse and had no power to the Jeep. Do the techs actually have to clamp the terminal connectors on and did so in reverse or did they just attach them incorrectly? It just seems odd that the larger anchor blade terminal is attached to the smaller wire for the aux negative lead.

Edit: Pulled both leads off and reconnected the larger ground wire back. Works as described above. Pics added for reference.

Just checking but in the pics the wire you have connected is actually the aux ground. You are saying you switched them and put on the wire with the stud correct?

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[Stuckinthesand]

Glad I found this thread. Great find by the OP.

My question is... for those that intend to drive in this condition permanently.... will you eventually remove the AUX battery altogether with it no longer needed? Or is there a need (possibly obvious one) to keep it installed that I'm missing?

I will remove the battery after warranty is up. I run a start stop eliminator so I don't have to remember to push the ESS button every time. I carry a jump pack with me so if the main battery is low I can at least get it started to get another battery.

 

[SlickRickMotoADV]

Just checking but in the pics the wire you have connected is actually the aux ground. You are saying you switched them and put on the wire with the stud correct?

Yeah that's what has me confused now. OP's original thread has a pic of "AUX ground disconnected" and it shows the "L bracket" type connector still connected as the main ground. Hoping someone can clarify this point.

 

[bohnster]

Just checking but in the pics the wire you have connected is actually the aux ground. You are saying you switched them and put on the wire with the stud correct?

Thanks, but it's not though, at least on my JL. That's what I was trying to say before. My terminal connectors appear to be reversed on the two wires. Hopefully that's the only "Friday special" that I got. The thicker wire is the main body ground and the thinner wire is the aux negative. I watched Brandon's videos and a few others then went out to mine to do this mod. Traced the wires and went "WTF?" My thicker wire that runs to body ground has the terminal connector that you see Brandon and others pulling off to disconnect aux negative. I did the mod as pictured and all works fine.

 

[Stuckinthesand]

Yeah that's what has me confused now. OP's original thread has a pic of "AUX ground disconnected" and it shows the "L bracket" type connector still connected as the main ground. Hoping someone can clarify this point.

I just double checked on a few different threads and did a YouTube search on testing the aux and every one has that single wire pulled off the stud bracket.

 

[Stuckinthesand]

Thanks, but it's not though, at least on my JL. That's what I was trying to say before. My terminal connectors appear to be reversed on the two wires. Hopefully that's the only "Friday special" that I got. The thicker wire is the main body ground and the thinner wire is the aux negative. I watched Brandon's videos and a few others then went out to mine to do this mod. Traced the wires and went "WTF?" My thicker wire that runs to body ground has the terminal connector that you see Brandon and others pulling off to disconnect aux negative. I did the mod as pictured and all works fine.

That sucks. Glad you figured it out. Threw me for a loop for a second.

 

[bohnster]

Yeah that's what has me confused now. OP's original thread has a pic of "AUX ground disconnected" and it shows the "L bracket" type connector still connected as the main ground. Hoping someone can clarify this point.

I may just be the anomaly. It's the thicker wire that you want to keep connected and you should be able to trace it over to the body ground point.

 

[Jebiruph]

Thanks for pushing though on this. Oddly, my main battery ground seems to be the opposite of what's shown in the videos in the other ESS disable post. Thinking I might have missed a twist in the pairing withou

Thanks for pushing though on this. Oddly, my aux negative disconnect and main battery ground seem to be the opposite of what's shown in the videos in the other ESS disable post. Thinking I might have missed a twist in the pairing without pulling everything out, I followed the instructions anyway for pulling that lead off after pulling the fuse and had no power to the Jeep. Do the techs actually have to clamp the terminal connectors on and did so in reverse or did they just attach them incorrectly? It just seems odd that the larger anchor blade terminal is attached to the smaller wire for the aux negative lead.

Edit: Pulled both leads off and reconnected the larger ground wire back. Works as described above. Pics added for reference.

Here's my post about the cable change https://www.jlwranglerforums.com/forum/threads/ess-battery-cable-change.86624/

 

[Jebiruph]

Glad I found this thread. Great find by the OP.

My question is... for those that intend to drive in this condition permanently.... will you eventually remove the AUX battery altogether with it no longer needed? Or is there a need (possibly obvious one) to keep it installed that I'm missing?

There's no need to keep it, but it doesn't hurt anything and as long as you keep it charged you will always have a backup battery available if needed.

 

[bohnster]

Here's my post about the cable change https://www.jlwranglerforums.com/forum/threads/ess-battery-cable-change.86624/

Well, crap, I must have been absent from class that day. Thanks for the update!

 

[Jerrybizzle]

How’s this working out? Still just fine? I tried this on my 2019 which I’ve had almost 3 years and it went haywire. Could my main battery be toast? I’ve been noticing hard starts as of late so wanted to try to get rid (systematically not physically) of the aux battery if it will help the main batteries life out. I’ve had ess off with my tazer about the entire 37k miles so it shouldn’t have much wear but know they last varying times, so at 3 years old I thought the aux was crap. Pulled fuse 42, removed aux ground and tried to restart. It acted like there was no power at all. Checked with dmm and it was reading at like 6v on my main battery. Could my aux battery be helping my main battery out? May try again tomorrow night to see if it was a one off deal and just random or if my main battery is actually done for.

 

[Jebiruph]

How’s this working out? Still just fine? I tried this on my 2019 which I’ve had almost 3 years and it went haywire. Could my main battery be toast? I’ve been noticing hard starts as of late so wanted to try to get rid (systematically not physically) of the aux battery if it will help the main batteries life out. I’ve had ess off with my tazer about the entire 37k miles so it shouldn’t have much wear but know they last varying times, so at 3 years old I thought the aux was crap. Pulled fuse 42, removed aux ground and tried to restart. It acted like there was no power at all. Checked with dmm and it was reading at like 6v on my main battery. Could my aux battery be helping my main battery out? May try again tomorrow night to see if it was a one off deal and just random or if my main battery is actually done for.

Based on your description, it looks like the aux battery is helping a bad main battery.

 

[Mikester86]

How’s this working out? Still just fine? I tried this on my 2019 which I’ve had almost 3 years and it went haywire. Could my main battery be toast? I’ve been noticing hard starts as of late so wanted to try to get rid (systematically not physically) of the aux battery if it will help the main batteries life out. I’ve had ess off with my tazer about the entire 37k miles so it shouldn’t have much wear but know they last varying times, so at 3 years old I thought the aux was crap. Pulled fuse 42, removed aux ground and tried to restart. It acted like there was no power at all. Checked with dmm and it was reading at like 6v on my main battery. Could my aux battery be helping my main battery out? May try again tomorrow night to see if it was a one off deal and just random or if my main battery is actually done for.

Are all of your Service Bulletins and recalls up to date? I thought there was an update that would allow the Jeep to start with a weak or dead Aux battery. Maybe this is your scenario and the Aux battery is weak?

 

[OldBlue]

Wow, so a simple fuse pull, aux battery cable disconnect, and we're good to go, huh? Not that the jumper was a big deal, but this is even easier! I'll have to remove the jumper and fuse and try it out myself. Thanks Jerry and others!

 

[Jerrybizzle]

Based on your description, it looks like the aux battery is helping a bad main battery.

It was strange for sure. I’ll try it one more time later, but it was definitely weird. Thanks again for all the work you’ve done on this topic. Read about 25 pages of the original thread on this then found this simpler way of achieving it.

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