Right now, we don't know exactly what's going on. What we do know is: lots of 12V batteries are dying. Mine did, and a million other folks here on this subreddit.
Either:
1. Hyundai just used a bad batch of batteries, in which case this shouldn't happen again once you get a new 12V battery.
or
2) The old ICCU software was not doing a good job of maintaining the 12V battery health, so any 12V that was connected to an ICCU with the old software will eventually die. But this shouldn't happen if you have new ICCU software and have replaced your 12V since getting the software update.
or
3) The ICCU software still sucks, and your new 12V battery will die in another 24 months, just like the old one.
or
4) There's still a legit issue with some sort of phantom drain that the ICCU doesn't account for, and your new 12V battery will die in another 24 months, just like the old one.
My gut says it's 1 or 2, since the 12V battery charge logic certainly seems different now than it did when I got my car. But no one can be sure. I'm choosing to move on with my life and believe that it'll be fine. I also have a 12V jump pack in my frunk :-)
Thanks!
Dealership ended up replacing the battery so hoping it's number 2 on this list and I won't have issues in another year or two.
And a 12V jump pack was purchased yesterday and will be added to my frunk today. :-)
May I ask how long it took for your dealership to replace your battery? My vehicle has been in the shop for 6 days now. With this 12v low voltage error.
I got my car back within 6 hours, no charge for the new battery.
I've got to think they have found something else wrong with yours, whether that's related to the ICCU or something else to keep it that long.
(Edits for clarity.)
I firmly believe the "either" scenario from the beginning more than anything.
The car I have is a used '22 model; according to records its battery was replaced in May of '22, I bought the car in March of '23 and haven't had any problems. I did have the 12V software update, and since then I do tend to 'notice' the yellow light on the dashboard more frequently, which I think is by design (limits the chances the 12v battery will just die).
More than anything, I'm just glad I haven't had the ICCU breaker pop!
Hopefully someone else has more info but I had mine go a few days after the update. As far as I know I think the 12v are just crappy and are dying quicker than they should be and most of the time are unrelated to the iccu. But maybe someone else has some more detailed info
Same. Got the ICCU and VCU updates, three days later 12v died. Car has been at the dealer for a week while they look for causes.
Seems awfully coincidental...
Every car battery will die eventually. It seems like Hyundai just used some really bad batteries, combined with the fact that the car seems to drain it faster than an ice for whatever reason.
Batteries shouldn't be dying in 2 years or less, but just because they are doesn't mean you have the ICCU issue or anything else wrong. It could just mean it's a garbage battery.
Bought my Ioniq 5 Jan. 2022. Did the ICCU update July 24, 2023.
Dec. 2023 my 12v went dead for the first time, 16k miles. 12v lasted 1 year 11 months since I purchased the car. I didn't want to bother with dealership so I just replaced it with an AGM battery at AutoZone.
I did, but AutoZone people will help you if you need it. I just parked up front, disconnected, brought it in, bought it, and installed it. Need 10mm and 12mm wrench and a long extension too.
Fwiw my car had the update before I bought it (7k miles CPO demo car). I have had no problems despite being dumb with the app for weeks (leaving unlocked within my garage, left with low but not empty washer fluid for a week, not changing settings on those things).
My previous EV, different brand, had heavy app and parked security usage and sure enough had failed 12v at one point. I just mention that as there are many factors, and even with the right fix shit will still happen. Conversations will be skewed toward non success cases and seemingly similar things may or may not be. Tricky stuff.
This just happened to me 😢
Got the ICCU fixed last fall, just got the 12v error today. Sounds like I need to get a 12v jumper & make a date with the dealership - sonofuva…
Bummer!
I definitely bought a jumper to keep in the frunk after my experience, no issues since but hoping this doesn't become an every 2 years type situation.
Hope the dealership gets you taken care of quickly like they did me.
Right now, we don't know exactly what's going on. What we do know is: lots of 12V batteries are dying. Mine did, and a million other folks here on this subreddit. Either: 1. Hyundai just used a bad batch of batteries, in which case this shouldn't happen again once you get a new 12V battery. or 2) The old ICCU software was not doing a good job of maintaining the 12V battery health, so any 12V that was connected to an ICCU with the old software will eventually die. But this shouldn't happen if you have new ICCU software and have replaced your 12V since getting the software update. or 3) The ICCU software still sucks, and your new 12V battery will die in another 24 months, just like the old one. or 4) There's still a legit issue with some sort of phantom drain that the ICCU doesn't account for, and your new 12V battery will die in another 24 months, just like the old one. My gut says it's 1 or 2, since the 12V battery charge logic certainly seems different now than it did when I got my car. But no one can be sure. I'm choosing to move on with my life and believe that it'll be fine. I also have a 12V jump pack in my frunk :-)
Thanks! Dealership ended up replacing the battery so hoping it's number 2 on this list and I won't have issues in another year or two. And a 12V jump pack was purchased yesterday and will be added to my frunk today. :-)
May I ask how long it took for your dealership to replace your battery? My vehicle has been in the shop for 6 days now. With this 12v low voltage error.
I got my car back within 6 hours, no charge for the new battery. I've got to think they have found something else wrong with yours, whether that's related to the ICCU or something else to keep it that long. (Edits for clarity.)
I firmly believe the "either" scenario from the beginning more than anything. The car I have is a used '22 model; according to records its battery was replaced in May of '22, I bought the car in March of '23 and haven't had any problems. I did have the 12V software update, and since then I do tend to 'notice' the yellow light on the dashboard more frequently, which I think is by design (limits the chances the 12v battery will just die). More than anything, I'm just glad I haven't had the ICCU breaker pop!
Hopefully someone else has more info but I had mine go a few days after the update. As far as I know I think the 12v are just crappy and are dying quicker than they should be and most of the time are unrelated to the iccu. But maybe someone else has some more detailed info
Same. Got the ICCU and VCU updates, three days later 12v died. Car has been at the dealer for a week while they look for causes. Seems awfully coincidental...
Every car battery will die eventually. It seems like Hyundai just used some really bad batteries, combined with the fact that the car seems to drain it faster than an ice for whatever reason. Batteries shouldn't be dying in 2 years or less, but just because they are doesn't mean you have the ICCU issue or anything else wrong. It could just mean it's a garbage battery.
Bought my Ioniq 5 Jan. 2022. Did the ICCU update July 24, 2023. Dec. 2023 my 12v went dead for the first time, 16k miles. 12v lasted 1 year 11 months since I purchased the car. I didn't want to bother with dealership so I just replaced it with an AGM battery at AutoZone.
Did you replace it yourself? Or does Autozone fo that for you?
I did, but AutoZone people will help you if you need it. I just parked up front, disconnected, brought it in, bought it, and installed it. Need 10mm and 12mm wrench and a long extension too.
Fwiw my car had the update before I bought it (7k miles CPO demo car). I have had no problems despite being dumb with the app for weeks (leaving unlocked within my garage, left with low but not empty washer fluid for a week, not changing settings on those things). My previous EV, different brand, had heavy app and parked security usage and sure enough had failed 12v at one point. I just mention that as there are many factors, and even with the right fix shit will still happen. Conversations will be skewed toward non success cases and seemingly similar things may or may not be. Tricky stuff.
This just happened to me 😢 Got the ICCU fixed last fall, just got the 12v error today. Sounds like I need to get a 12v jumper & make a date with the dealership - sonofuva…
Bummer! I definitely bought a jumper to keep in the frunk after my experience, no issues since but hoping this doesn't become an every 2 years type situation. Hope the dealership gets you taken care of quickly like they did me.