It's Time to replace your JL's batteries when....

[Gee-pah]

this could almost be the tag line of some creative comebacks:

"you buy it."
"when the sun comes up."
"when you change the smoke alarm batteries."

But seriously, as it pertains to the 3.6L (and maybe moderators want this post under that forum) is there a litmus test of when it's a good time to have them taken in for service?

There certainly have been enough posts on how to test each battery's voltage. While parked and shut down, take all the cables off the main battery's negative post and put the negative side of your tester on those loose cables and the positive side of your tester on the main battery and that's your ESS/Aux battery's voltage.

Put all the cables back and take the one off the negative post that is closer to the passenger's side (i.e. the ESS/Aux negative cable) and put your tester up to the main battery's terminals and that's your main battery's voltage.

Don't forget to put those cables back the way you found them.

But it's not that simple as that as some of us haven't used our 3.6L JLs as much during COVID, and some of us have, and yet some of us have placed a trickle charger on the main battery terminals during this period of infrequent use: which BTW charges both batteries.

So what IS the litmus test for it making sense to get your batteries tested at the dealer?

Sponsored

 

[Bob Burd]

There's no one litmus test. There's two batteries and they can fail in various ways and since they power all car electricals, a failure can manifest itself in at least a dozen ways.

 

[aldo98229]

Unfortunately, the charging system and related wiring harness appear to be particularly frail, rendering the batteries that come from the factory fail-prone.

These would be bad enough on any vehicle, but more so on one that relies so much on electronics.

My guess is, either the aftermarket community will come up with sturdier replacement parts, or FCA will be forced to issue a recall at some point. Already there have been reports of JLs losing all power; some as soon as they drove off the lot. It will only take a handful of Jeeps to do so on the freeway for NHTSA to trigger an investigation.

Sponsored