Wrangler JL or JLU battery advice

[4WD]

My Wrangler has been giving early warning on the batteries - so will buy/carry the larger upper battery until the 100° summer passes …
A fused jumper is available to bypass that Aux14 battery (N1 to N2).
Anyone see a problem to just orphan that small battery - it’s a pain to get to and some bad press out there over this odd arrangement …
(figure the wimpy Aux14 will just die soon enough) …

 

[wings&wheels]

doesn't the small battery primarily support the stop/start function, while also supplying general power. so, we store our JL winters and the first time I disconnected the main battery (i didnt do my homework on the 2 batteries), when I went to bring the car back from hibernation, the stop/start was inop but otherwise the vehicle ran fine except for the s/s error message and single chime. 2+ years and no other issues.

ours is a manual and I think stop/start on a manual is ridiculous to the point of being dangerous....

 

[4WD]

doesn't the small battery primarily support the stop/start function, while also supplying general power. so, we store our JL winters and the first time I disconnected the main battery (i didnt do my homework on the 2 batteries), when I went to bring the car back from hibernation, the stop/start was inop but otherwise the vehicle ran fine except for the s/s error message and single chime. 2+ years and no other issues.

ours is a manual and I think stop/start on a manual is ridiculous to the point of being dangerous....

Seems to me it’s very low CCA and can only take work away* from the battery with ample CCA … keeping the large battery ready for endless S/S - which I turn off …

 

[wings&wheels]

Seems to me it’s very low CCA and can only take work away* from the battery with ample CCA … keeping the large battery ready for endless S/S - which I turn off …

makes sense...i know on my daily RR, i asked the dealer if they could turn off the s/s, and they said no.

when i picked the vehicle up, the advisor said 'your aux battery is discharged and will not recharge, your s/s/ won't work. would you like another appointment to have a new one installed?'

 

[Nuclear_42]

Don't over complicate things. The stock set up works fine. Replace the bad battery and move along.

 

[4WD]

Don't over complicate things. The stock set up works fine. Replace the bad battery and move along.

You have this setup ? You don’t do all this work and replace one cheap battery … it’s both - hard work shoving electronics around - and expensive batteries that can leave me stranded 22 miles down a deep sand peninsula where most can’t reach me …

 

[4WD]

makes sense...i know on my daily RR, i asked the dealer if they could turn off the s/s, and they said no.

when i picked the vehicle up, the advisor said 'your aux battery is discharged and will not recharge, your s/s/ won't work. would you like another appointment to have a new one installed?'

This is what some of the Jeep forum guys say - and yes some have issues with this odd configuration. (As has 1 of my engineers)

 

[D60]

I too have considered just deleting the second battery. The whole system overall is an overly complicated headache IMO

I think it's the Pacifica that got the same motor and ESS and doesn't have the second batt?

I really don't see any big reason for concern, and yet I haven't done it yet. Everything else I drive has a single battery.....

One thing you could do is leave the AUX14 and keep it disconnected. If your main batt dies the vehicle will start and run on the little one only. So, redundancy.....but you'd have to periodically check voltage on the AUX14 or it's like having a flat spare tire when you need it

 

[Nuclear_42]

You have this setup ? You don’t do all this work and replace one cheap battery … it’s both - hard work shoving electronics around - and expensive batteries that can leave me stranded 22 miles down a deep sand peninsula where most can’t reach me

Again a good battery should last you at least 36k miles or 3 years just like the oem. To do this task once every 3 plus years is no issue. Instead of modifying the jeep for no reason. Your aux battery dies it can be jumped via the main battery like any other car. The only way the aux battery will leave you stranded is of it completely dies. 90% of the time they just get low voltage and can be jumped.

 

[Nuclear_42]

My Wrangler has been giving early warning on the batteries - so will buy/carry the larger upper battery until the 100° summer passes …
A fused jumper is available to bypass that Aux14 battery (N1 to N2).
Anyone see a problem to just orphan that small battery - it’s a pain to get to and some bad press out there over this odd arrangement …
(figure the wimpy Aux14 will just die soon enough) …

If you truly want to learn about this system read all the pages in this thread.

Auxiliary Battery Jump

Apparently you can jump your own auxiliary battery from your main battery if stuck out on the trail or away from services. I did see a tip from another JL owner who showed jumping from another vehicle to the first terminal/auxiliary, but didn’t know you could just jump it yourself from the main...

www.jeepgladiatorforum.com

 

[4WD]

If you truly want to learn about this system read all the pages in this thread.

Auxiliary Battery Jump

Apparently you can jump your own auxiliary battery from your main battery if stuck out on the trail or away from services. I did see a tip from another JL owner who showed jumping from another vehicle to the first terminal/auxiliary, but didn’t know you could just jump it yourself from the main...

www.jeepgladiatorforum.com

Started Jeep today - got “aux switches disabled”
Going to pick up a large battery tomorrow and carry it in the back …
Don’t want to dig that buried battery out in 100° weather … its only 200 CCA for $150 … not everywhere … some have gone out in 2 years …
S/S is the most ignorant thing ever installed by an OEM … I turn it off and will do even more later …
Lastly - no batteries I can’t even see or maintain terminals on …
An 850 CCA AGM can handle a V6 and an all LED package …

 

[4WD]

confirmed online posts with owner of both a 2019 & 2021
H6 is original & some are upgrading to H7
(his 2019 replaced at 3.5 years like mine)

Original setup for perspective + new H7 AGM

 

[4WD]

Pulled the 700 CCA AGM
Installed an 850 CCA AGM
Left off the Aux14 ground
Pulled ESS fuse

 

[4WD]

Pulled the 700 CCA AGM
Installed an 850 CCA AGM
Left off the Aux14 ground
Pulled ESS fuse

View attachment 186481

That ended stop/start - but did not give stable voltage - took the wheel off and pulled the plastic liner back to fight this little joke of a battery out …
(QS for size comparison) … Voltage is stable now …

 

[4WD]

Just a heads up on internet information - some claim success by only removing an Aux14 ground and a fuse. Or just disconnecting the Aux14 and no jumper … I tried both and only got 12.7V
(are the YT boys even checking volts?)

So, after removing the Aux14 and installing the N1 to N2 jumper - I’m steady at 14.2V …

(used a 4Ga x 12” starter lead as jumper)

 

[GMBoy]

I disabled Start/Stop in our Gladiator with my Autel Scan tool that is capable of doing module settings. I did this last year and never removed the battery. Not sure if I should or not but for now I don't plan on doing anything with it.

 

[4WD]

Just a heads up on internet information - some claim success by only removing an Aux14 ground and a fuse. Or just disconnecting the Aux14 and no jumper … I tried both and only got 12.7V
(are the YT boys even checking volts?)

So, after removing the Aux14 and installing the N1 to N2 jumper - I’m steady

(used a 4Ga x 12” starter lead as jumper)

Just to finalize -
Have received feedback from several JLU owners that the stock setup has some bad history - Google searches show as well …
The single H7 AGM has been stellar with the Aux14 battery gone
(Removed via fender liner, taped leads, N1>N2 jumper)
Put fuse back in (idiot light) - S/S is available but I tend to turn it off …
The H7 (unlike the tiny battery) is in an easy to reach spot …
Happy with this change …

 

[4WD]

I disabled Start/Stop in our Gladiator with my Autel Scan tool that is capable of doing module settings. I did this last year and never removed the battery. Not sure if I should or not but for now I don't plan on doing anything with it.

What year is your JT ?

 

[JustTrynaHelp]

On our 2020 w/ 2.0 turbo, we were getting weird electrical stuff and the main battery was testing bad.

Replaced it and still had weird things happening.

After doing the research, disconnected the battery cable to the second battery and -poof - all issues vanished. Been that way for 6 months now.

Why they put the weak, rapid-fail battery in a place that requires either fender removal or disassembly of the fuse box seems, to me, a ploy for more service income at dealerships. Just going to leave it there.

Plenty of Youtube videos on how-to (and which cable, it actually varies) and it only cost a zip tie and a little electrician's tape.

Stop/start still works but we turn it off.

 

[4WD]

On our 2020 w/ 2.0 turbo, we were getting weird electrical stuff and the main battery was testing bad.

Replaced it and still had weird things happening.

After doing the research, disconnected the battery cable to the second battery and -poof - all issues vanished. Been that way for 6 months now.

Why they put the weak, rapid-fail battery in a place that requires either fender removal or disassembly of the fuse box seems, to me, a ploy for more service income at dealerships. Just going to leave it there.

Plenty of Youtube videos on how-to (and which cable, it actually varies) and it only cost a zip tie and a little electrician's tape.

Stop/start still works but we turn it off.

It’s absolutely horrible - one of our engineers did it from the top and that’s a goat roping too - I felt like it exposed more sensitive electronics to damage - so did the fender thing …