Wrangler JL or JLU battery advice

JustTrynaHelp said:
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.
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How’s the 2.0T been for you ?
Was leaning that way but found a $5k off sticker deal on the V6 …
 
4WD said:
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 …
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4WD said:
They are amazing - still on original batteries ?
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Replaced the main battery last winter - just to be safe as it tested only 575ca to a rated 700. Little battery is original and still in there.
 
4WD said:
They are amazing - still on original batteries ?
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Here she is, older photo did some things since such as window tint and such.

KIMG0078.JPG
 
4WD said:
How’s the 2.0T been for you ?
Was leaning that way but found a $5k off sticker deal on the V6 …
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It's been good so far; got it with about 35K and we're almost at 60K now. Got a good UOA on the last oil change, and the results were better than average.

I had my misgivings at first as I prefer the six cylinder also. But it has been solid and apparently has been used in Europe for several years.

We also live at higher altitude, so it's nice not to lose power in the hills like you would with a normally aspirated engine.
 
JustTrynaHelp said:
It's been good so far; got it with about 35K and we're almost at 60K now. Got a good UOA on the last oil change, and the results were better than average.

I had my misgivings at first as I prefer the six cylinder also. But it has been solid and apparently has been used in Europe for several years.

We also live at higher altitude, so it's nice not to lose power in the hills like you would with a normally aspirated engine.
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Buddy of mine has a '21 Jeep with the 2L and he is happy as well - the turbo in high altitudes is a plus for sure.
 
Update - after much head scratching - and pulling the Aux14 - this was not just a wise move - but essentially done at no cost. Put the $130 I saved into a better main AGM - and only needed a $10 starter cable to tie N1 & N2 together … In fact - in the past - if I used the winch - it stayed in a battery warning mode for a day or two. Used it a couple weeks ago - no messages at all …
Availability and warranty is alsomuch simpler now …
No regrets 😉
 
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There’s a risk that the 2 battery system can exhibit the weaker battery pulling the other down. A buddy of mine just went through this. We upgraded the main to an H7 and dropped the fuse and jumper for the aux. we found an H7 with the same amp-hours as the previous combination of both. Good to go, running well.
 
meep said:
There’s a risk that the 2 battery system can exhibit the weaker battery pulling the other down. A buddy of mine just went through this. We upgraded the main to an H7 and dropped the fuse and jumper for the aux. we found an H7 with the same amp-hours as the previous combination of both. Good to go, running well.
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It was kinda creepy having that tiny battery buried to where you could not even see the terminals …
Way over priced too …
 
4WD said:
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) …
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Our '20 was the same, then left us stranded. Did the research, disconnected the small battery and replaced the main one. No issues since for the last 8-9 months.

We usually turn off the stop/start nonsense.

Check out Youtube for videos on this, Jeep uses different electrical setups so s/s may or may not work, and you may have to disconnect a different battery lead than in the video (ours was opposite of most)

That small battery is a pain, either disassemble the fuse box or remove the fender....come on Stellantis this is just a ploy to collect more service $$
 
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