JK battery life?

    My battery died on the beach 2 weeks ago and I figured that I left my ignition "on" instead of "accessory" and didn't think too much of it. Until today... No start and the voltage was below 11v. Jumped it with the XJ and drove to get gas and idled a bit, probably 20 minutes. 3 hours later, no start and voltage is at least below 11.5v (because that's the safety limit for my switch panel). My JK was built in 2011 so I'm at 3 years on the battery, with no abuse... only one light pull on the winch (on ice).


    Nothing has changed, electrically, in the Jeep since the end of August when I added a fuse block to supply the compressor and ham radio. Both of which run off of relays (from the switch panel and on ignition power).


    Are JK batteries that bad or is this a fluke? And where should I look for a replacement? I had a Red Top in the XJ that served me well, but the internet advice has said they're not as good as they used to be.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    im at 42k on my 2012, and though i don't have any "heavy load" mods (winch, compressor) i do run the radio with amplifier for hours at a time...with no problems. i typically will go 45-1.15 hours before starting back up to charge. ive used it to jump start several vehicles too.

    Thanks for the input, I was hoping you'd post. :) My JK is almost to 40,500 miles, so right behind you. This battery thing is annoying but at least it didn't happen out west... gonna try picking up an AGM battery first thing in the morning. I'll have to jump it, it's dead again...

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    My JK will run two coolers for several hours on the beach and still be ok. If I have the key in accessory though, it kills the battery quickly. I think the MyGig radio thing draws a lot of amperage. It seems like JK's use about twice the power as the simpler TJ/YK/XJ/etc.


    Did you try trickle charging it to recover it? I doubt the battery is done but then again, batteries seem to suck more and more in recent years.

    I've got an Optima red top, now... the H6 size AGM batteries are out of stock at the 3 nearest stores, and the 34 size batteries have the terminals on the wrong side, so I ended up with a 34R red top. $20 more than the regular AGM battery but has more juice and hopefully I'll have good luck with it. The guy at Advanced Auto said he's been running one in his car for 5 years and has a big audio system.


    The battery machine there said it was only putting out 11 CA. lol... but at 11.8V. This was after running for 10 minutes. I'll let it sit for a while and see what happens in a few hours. I don't know what could be pulling that much power to kill the battery in just 3 hours.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Quote from keith_c

    If you have access to a DVM with a DC Amps function put it inline with one of the battery cables.



    Nope... not cool enough to have one of those. Time will tell, if the new battery is drained tonight or tomorrow, then I'll start looking for a short somewhere.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Quote from ForMud


    Dumb question...Is the charging system working?


    I've had the best luck with a deep cycle battery, their designed to be taken down to zero amps and then recharged many times.



    Sadly, I have the basic dash so don't know how well the alternator is working... only gauges are engine temp and fuel level. I wanted the EVIC dash but didn't get it. Ah well... (yes, yes, I know... I can use a multimeter).



    Last night it started fine, and drove 45 minutes to Cecilton, MD for a PTSD benefit. The Jeep sat for 6 more hours and started fine. Drove 5 minutes to a friends place and hung out for a few more hours, then started fine again and drove 45 minutes home. Sat for 12 hours and started fine again. I know my old Optima was a good battery, but if there was a drain on the system, I think it would have died either last night or this morning. I'll chalk this up to a dead battery.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Quote from ForMud


    For peace of mind.....I think I would swap it......That and buy a meter. :mrgreen:



    Scroll up, I replaced it yesterday. :razz:

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Bummer... at least I'm not alone. Thanks :)

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    I work for Johnson Controls in Middletown. We make lead acid batteries. There are a number of things that could end a batteries life early, most of them are warranty related issues (broken straps and +/- plates touching are the main ones). If it's not under warranty, you're SOL.



    My company owns Optima Batteries. I've been using them for many more years than I've worked here. As far as I'm concerned, they are the best battery on the market. They are in my boat and all my cars. My deep cycle marina batteries are still going strong after 4 years and I've never been stranded in a car or boat because of a battery related homicide.



    FYI... You guys are correct, the average battery life is 3 years before the lead plates start breaking down inside the battery. If you store the vehicle in a garage, the battery will probably last longer. If it's outside 24/7, probably shorter. The extreme hot and extreme cold is what makes the acid eat away at the lead plates faster. Remember, when you're wheeling and jarring an older battery around, the plates will disintegrate faster because of the contact with each other.

    When a man lies, he murders some part of the world.  These are the pale deaths, which men miscall their lives.  All this I cannot bear to witness any longer.  Cannot the kingdom of salvation, take me home.

    Edited once, last by DJS DAD ().

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