[joebruin77]

Has anyone replaced their 12v battery proactively? With my old Tesla, I used to change the 12v battery proactively once every 2 years, just to make sure I was never stranded by a dead 12v. I thought of this as cheap insurance.

Would you recommend replacing the iX 12v battery proactively? If so, how often should it be replaced?

If not, why not?

Any ideas roughly how much it would cost to have the 12v battery replaced at my local BMW dealer?

Thank you,
Joe

[Barry123]

Just an educated guess, but I suspect the car will tell you when it needs replacement.

I had a 2015 Model S. The first 12V battery lasted 6 weeks! The next one 2 years. The next one 4 years.

Teslas had a very poor charging algorithm for the first several years. That, in combination with the absurd vampire drain necessitating 5 charge cycles per day, caused the 12V battery to fail frequently. As there is no vampire drain in the BMW, there's no reason the the battery not to last its expected life.

[exxxviii]

I don’t think we have enough years on the iX to know yet. It all depends on how good the LV battery management is. My last BMW devoured batteries at about every 3 years. Our minivan was lucky to get 3 years. My last car went 5 or 6 years on its battery. Our SUV is four years on its battery with no hiccups. Honestly I would just wait and see - that’s my plan.

[joebruin77]

Is the iX able to detect problems with the 12v battery and give you a warning if it needs to be serviced or replaced? And is this a reliable system?

I am trying to avoid a situation where my 12v battery suddenly dies and I am left stranded.

[exxxviii]

Originally Posted by joebruin77

I am trying to avoid a situation where my 12v battery suddenly dies and I am left stranded.

The only cases I have read of this are 2 scenarios, neither of which is solved by a proactive replacement.

1. The BMS failed to keep the 12V battery charged
2. Random 12V failure unrelated to age or recharging management

[darylp310]

Originally Posted by joebruin77

I am trying to avoid a situation where my 12v battery suddenly dies and I am left stranded.

Anecdotally, I just haven't heard about this happening with BMW EVs. You read about this with Teslas, MachEs, and sometimes Ioniq5s. So maybe as a MachE owner you are more aware/sensitive to it?

[thebishman]

The fact that Tesla 12V batteries only last about 2 years is probably indicative of the ‘quality’ (not!) of the batteries being installed.

I’m not worried in the least about the 12V in my iX; I hope/suspect it will last at least 4-5 years, and that when it does start to fail, it will let me know.

Question: does anyone know if something like this is useable on the iX? It’s something else to keep in the ‘Emergency box’ when on an extended journey if it is compatible.

[exxxviii]

Originally Posted by thebishman

Question: does anyone know if something like this is useable on the iX? It’s something else to keep in the ‘Emergency box’ when on an extended journey if it is compatible.

You didn’t post a link, but I am wondering if you meant something like this: https://www.amazon.com/dp/B09HYVM6ZT?th=1

Yes, these work for all BEVs and will get you going again if your 12V fails. I carry one in my car.

[MAMOHT]

CarData shows you the health of that battery. Not sure whether that actually works well or not though. I’d assume that BMW sends some kind of email or something when that health number goes down.

[ricerboi]

Originally Posted by thebishman

The fact that Tesla 12V batteries only last about 2 years is probably indicative of the ‘quality’ (not!) of the batteries being installed.

I’m not worried in the least about the 12V in my iX; I hope/suspect it will last at least 4-5 years, and that when it does start to fail, it will let me know.

Question: does anyone know if something like this is useable on the iX? It’s something else to keep in the ‘Emergency box’ when on an extended journey if it is compatible.

Not necessarily. Teslas have a lot more passive systems like Sentry Mode and there’s a lot more load on the 12V battery even when not driving.

iX’s are pretty easy on the 12V as there are none of those active remote monitoring features short of laggy remote cameras and laggy remote functions.

I’m at 78k miles/2.5 years now and nothing tells me the 12V is even close to needing replacement.

[darylp310]

Yeah, I was going to mention the same thing. The Tesla tries to do a lot things when the car is not running which is very convenient (dog mode, camp mode, sentry mode, summon mode, actively powered USB ports, Wifi for downloading updates, etc.) These systems make it tricky to know how much to keep the low voltage battery charged. I can even imagine a scenario where people might inadvertently be draining their low voltage battery just by keeping their fob too close to the car and unknowingly waking/sleeping all the time.

The BMW system is the complete opposite. For better or for worse, it is still pretty old fashioned, and you can't do much anything with the car until you push the ON button! And then it falls asleep and rarely wakes up for any cool, unattended operations!! As a technophile, I prefer the Tesla approach, but I also appreciate how conservative BMW is about using batteries as little as possible, so I will never be surprised with phantom drain!

I'm hopeful that Neue Klasse can be more of a compromise with the innovative software systems of Tesla, and the extra care and safety that BMW is known for. If it's designed with care we should be able to have both great electronic features + great battery health!!

[Bmwno6]

Originally Posted by exxxviii

You didn’t post a link, but I am wondering if you meant something like this: https://www.amazon.com/dp/B09HYVM6ZT?th=1

Yes, these work for all BEVs and will get you going again if your 12V fails. I carry one in my car.

How and where would you connect it on the iX ?

[exxxviii]

Originally Posted by Bmwno6

How and where would you connect it on the iX ?

This is where BMW made the iX a total PITA with the hood. You would need to open the hood and directly connect it to the battery - very difficult due to engineer idiocracy.

[darylp310]

Timely article on why 12 volt batteries often fail in EVs: https://insideevs.com/news/752720/ev...tery-problems/

[thebishman]

Originally Posted by exxxviii

You didn’t post a link, but I am wondering if you meant something like this: https://www.amazon.com/dp/B09HYVM6ZT?th=1

Yes, these work for all BEVs and will get you going again if your 12V fails. I carry one in my car.

Sorry about forgetting to post the link, but you choose the exact one I was looking at! lol

[thebishman]

Originally Posted by darylp310

Yeah, I was going to mention the same thing. The Tesla tries to do a lot things when the car is not running which is very convenient (dog mode, camp mode, sentry mode, summon mode, actively powered USB ports, Wifi for downloading updates, etc.) These systems make it tricky to know how much to keep the low voltage battery charged. I can even imagine a scenario where people might inadvertently be draining their low voltage battery just by keeping their fob too close to the car and unknowingly waking/sleeping all the time.

The BMW system is the complete opposite. For better or for worse, it is still pretty old fashioned, and you can't do much anything with the car until you push the ON button! And then it falls asleep and rarely wakes up for any cool, unattended operations!! As a technophile, I prefer the Tesla approach, but I also appreciate how conservative BMW is about using batteries as little as possible, so I will never be surprised with phantom drain!

I'm hopeful that Neue Klasse can be more of a compromise with the innovative software systems of Tesla, and the extra care and safety that BMW is known for. If it's designed with care we should be able to have both great electronic features + great battery health!!

Since occasionally we’ll travel for about 3-4 weeks at a time, I’d hate to leave a Tesla at the airport due to the vampire drain. I’d be constantly afraid of getting back to a drained 12V and/or HV battery.
Hence I’d far prefer to park the iX at the airport long term knowing it’s going to start when we get back.

[jono987654321]

Originally Posted by exxxviii

You didn’t post a link, but I am wondering if you meant something like this: https://www.amazon.com/dp/B09HYVM6ZT?th=1

Yes, these work for all BEVs and will get you going again if your 12V fails. I carry one in my car.

Where are the terminals to connect one of these to be found, please?

[exxxviii]

Originally Posted by thebishman

Sorry about forgetting to post the link, but you choose the exact one I was looking at! lol

And I own that exact one - my dad has one too, and I put them in all our family cars. I used it once to jump a gas car, and it was perfect.

Originally Posted by jono987654321

Where are the terminals to connect one of these to be found, please?

You have to connect it directly to the battery. It would be nice if BMW had secondary terminals, but nope.

[jono987654321]

So, presumably under the bonnet/hood? Do you carry a broom handle to prop it open?

[exxxviii]

Originally Posted by jono987654321

So, presumably under the bonnet/hood? Do you carry a broom handle to prop it open?

Yes, under the hood. And no, I do not have anything to prop it open. Though I could use one of my umbrellas. I have it as a disaster prevention and don’t ever expect to use it.

[javapro]

Originally Posted by jono987654321

So, presumably under the bonnet/hood? Do you carry a broom handle to prop it open?

Just invest in these safety pins and there will be no need for a broom or anything like it - https://www.bmwpartscenter.com/oem-parts/bmw-pin-813010-83305a3cd29 (part# 83-30-5-A3C-D29). These are what BMW technicians use to prop open the hood in the iX.

[Barry123]

Originally Posted by thebishman

Since occasionally we’ll travel for about 3-4 weeks at a time, I’d hate to leave a Tesla at the airport due to the vampire drain. I’d be constantly afraid of getting back to a drained 12V and/or HV battery.
Hence I’d far prefer to park the iX at the airport long term knowing it’s going to start when we get back.

Based on your listed location, you're about 30 miles from the airport, which is about the same distance I am from our airport. If a trip is longer than 3 days (which is almost always for me), I take an Uber/Lyft. Not only is it more cost-effective, but then I don't worry about my car (battery, vandalism, theft, etc.)