I'm wondering about this. My Deefer just hit 4 years old (and out of warranty).

Should I just proactively replace the battery? Bite the bullet. Spend the money.

Is that wasteful & insane ?

Getting no odd warning or issues other than the odd shutdown message when sitting in the car listening to the radio with engine off after a while, but prior Land Rovers have burned me in this regard.

This under the seat location is -- a disaster if your battery dies, is it not?

I have this premonition that some morning I'm going to walk out, it'll be dead, and the passenger seat won't move and I'll be using the jaws of life on the seat rails to remove the passenger seat. I guess the idea is that you hook the car up to power and move the seat that way. What if the seat doesn't move? Didn't someone on here have a story about the seat not cooperating ?

 

NO, it is not. I change batteries on my cars every 4 to 5 years (and most recently trending to do it every 4 years), even if I have no issues with it. This is a preventative measure and squeezing out the last ampere out of a battery so you can get stranded at the supermarket because the car won't start is just not worth it to me. It also avoids having all kinds of electronic gremlins that no one can diagnose which then go away when you change out to a new battery. To me it's not much different than changing out tires before they hit the wear bars, because the car feels like it has less traction in wet weather, or has a lot of road noise.

So no, changing your battery prophylactically every 4 years is neither wasteful nor insane.

 

My battery was replaced three years after I took delivery. I'd go ahead and get a new battery regardless. Many people with Defenders have needed new batteries around the 3-4 year mark. It is a pain to remove the battery as I'm almost positive the passenger seat has to be taken out in order to fully remove the battery.

 

There's nothing insane about performing preventative maintenance... especially if it helps you actually sleep better at night.

 

I did replace the battery after 3.5 years.
I also bought an battery tester to see how this battery will hold up, and on a point if it will weaken I can replace it as a precaution.
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3.5 years here too. Software upgrades would not load due to the weak battery. But it still passed some mandatory JLR charging level test so I had to pay for a new battery despite it still being under warranty. If the battery is too weak to install software updates, then IMO it should have been replaced under warranty.

 

Good info. I’m getting ready to replace my battery on my 2021. My research from the forums shows I need an AGM battery, Interstate Group 49 which is 850CCA. Can anyone confirm or share specifics on the battery you chose.
Thanks

 

Change it every 4 to 5 years. These cars will put out a lot of messages when the battery gets weak.

 

Good thoughts from all - I think I'm on borrowed time. Will swap it out.

 

I think unless you start getting weird and wonderful electrical gremlins, you’re good to go I think. I’m pro preventative maintenance but I’ve only ever replaced batteries after they give up the ghost.

I have a jump starter and a set of flares behind the second row seats. I’ve never field tested it but once you get a jump from something, you’ll slide that seat forward and get the old battery out.

These AGM batteries a big fatties.

nothing in the GAP tool that allows you to check it, other than to see the voltage it’s got. All the battery live values are for the 48v MHEV juicer.