2023 Hyundai Ioniq 5: battery drain or dead battery

Filed Mar 18, 2026 · Electrical · WA

The vehicle is a Hyundai Ioniq 5 electric vehicle. There have been known issues with the integrated charging control unit (ICCU) failing suddenly rendering the car inoperative; I just took it to the dealer and they confirmed a fault with the ICCU. I am up to date with multiple prior ICCU recalls and updates. Leading up to this, a few months ago my 12V battery died unexpectedly at ~22000 miles and I had it replaced. The ICCU charges the 12v battery so I wondered if there was an ICCU issue but the car otherwise was operating fine. Overnight while charging with a level 1 charger at home recently, the car stopped charging overnight unexpectedly. A couple days later I plugged in to charge at home again and got a message "charging unsuccessful", and on the dash I received a message that said "check electrical vehicle system" which went away when I unplugged the car. I tried a different level 1 charger from my wife's car and received the same "charging unsuccessful" message. Interestingly that charger no longer seems to work on her car, so it's possible that my car damaged the charging unit. I then went to try a level 2 charger maintained by the city of Seattle which was operative and had power when I plugged in. On plugging in, I received the same "charging unsuccessful" message and then the light on the level 2 charger went off and the level 2 charing unit lost power. Again, it appears that the fault on my car may have damaged an external charging unit. Thankfully I was still able to drive the car to the dealer where the ICCU failure was confirmed and am in the process of replacing it (they don't have the parts in house and told me the current wait is less than a week though previously had been sometimes months). A service rep told me many customers had the failure happen suddenly with a loud "pop" while the car was in motion causing them to limp to the side of the road or leaving them stranded.

Filed Mar 9, 2026 · Electrical · NC

12 volt battery keeps dying for normal reason. It was replaced last year. I have to jump it a few times a day. I'm afraid it will die while I'm driving. I was told at the dealer that it was because I was charging my car in the cold and the 12 volt battery will disconnect to avoid a fire. It was winter. Now we have in 80 degree temperature and the 12 volt battery is dying more frequently

Filed Dec 29, 2025 · Electrical, Engine · VA

I purchesed the Hyundai ionic 5 2023 from hyandai dealer ship. It had 42 k miles. The car ran good. So I got it. They promised me before the I bought they would charge it up free. When I signed the paper they said they couldn't charge it for me. I drove 5 miles the original battery died. I almost got to accudent only 5 miles away. I figured it was original battery. I change battery. I get tow truck to take home i put new battery in it. Then 5 days later the main iccu stopped charging. Another 12 bolt battery drain. They new it had that problem. Two batteries are main iccu won't charge. They make me sign paper buy as is i didnt think it would die 5 miles later they new it had a serious problem I look on internet the same car had recalls for the same car not on mine My car should have been recalled I heard 1000 s were affected with the same problem. They new it would fail on me thars why they get me to sign the papers. I hooe it's not 21 k down the drain I hope i dont have to spend 15 k on new iccu.

Filed Dec 1, 2025 · Electrical · IL

12 volt battery keeps dying. I have had the car for 2.3 years and am now on my 4th 12 volt battery.

Filed Oct 25, 2025 · Electrical · TN

12 volt battery dead. Interior lights don't come on. Vehicle won't start. 1. 1/8/24: orange 12V light coming on repeatedly, meaning battery not charging. Dealer, Hyundai of Cool Springs, found battery would not hold charge. Replaced battery. Afterwards, orange light still came on sometimes, but dealer advised to ignore it. 2. the federal safety agency recall for ICCU software problem affecting battery charging, Hyundai Recall 257/021G. Dealer fixed problem 3/28/24, 41D043R0 .4. Afterwards, orange light still came on sometimes, but dealer advised to ignore it. 3. Hyundai recall #9B5 of 8/1/24, software problem in VCMS affecting battery charging. Dealer, Hyundai of Cool Springs, updated VCMS 40D097R0 .3 on 9/10/24 Afterwards, orange light still came on sometimes, but dealer advised to ignore it. 4. the federal safety agency Recall 24V‑868 of 11/18/24, ICCU causing battery not to charge. Dealer, Hyundai of Cool Springs, updated VCU and ICCU, 40D229R0 .7 and 41D225R0 .4 on 1/23/25. Afterwards, orange light still came on sometimes, but dealer advised to ignore it.

Filed May 12, 2025 · Electrical, Transmission · GA

2023 Hyundai Ioniq 5 ICCU failed with DTC P1A9096 which renders the vehicle in limp mode once the 12V battery drains. This is a major issue which keeps happening even after severals recalls with software updates related to this problem. When this incident happened i had gotten all the recalls and software updates available for the entire care and still it failed prematurely at 35K miles.

Filed Jan 25, 2025 · Electrical · AL

After an ICCU recall was mitigated, vehicle charging failed before achieving requested charge level. I asked for 80% and I noticed that it only charged to 72%. After driving for a few minutes, vehicle appeared to enter limp mode and then the 12 volt battery died disabling the vehicle. I had to provide an external 12 volts in order to get the vehicle back into my garage so I could notify the dealership. Dealership indicated it would be about 6 weeks before The car could be diagnosed, let alone fixed.

Filed Jan 13, 2025 · Electrical · CO

There was no major safety issue in this instance. My concern is this poses a severe risk if it happened while driving. The car was on and in ready to drive mode but was parked in the garage with climate control on while loading it for going to school. At somepoint between trips to the car over 20 minutes it died with no warning. Some lights behind buttons, the interior lights, and the screens were on but blank. Not a single button in the car would respond. Including hazards or opening the trunk or closing the charging port door. Lights like the LED for the overhead light button blinked and the charging indicator by the charging port blinked a pattern of 1 longer flash and 8 shorter flashes. The car would not shut off or on again another button that was completely unresponsive. The lights and screen stayed on for at least 30 minutes before I left with a Lyft to get the kids to school. An hour and a half later everything was off and it seemed to have no power. At that point I did figure out how to jump it and get it to the dealer. The dealer claims the 12V battery died and that was the only issue and completed the 2 open recalls. There was no indication when I started the car that anything was wrong or the 12v battery was low or needed replacing. There are apparently no error codes from it completely failing while in ready mode. I was only told this happened because it was in park and the 12V battery failed while it was on and parked, if I had been driving I would still have use of the vehicle as the recall outlined for a failed ICCU when the 12V battery drains. They can find nothing else wrong but my concern is that a failed 12V battery could cause this while driving. I was told simply it cannot happen because the software handles it differently when driving. I hope that is correct.

Filed Nov 11, 2024 · Electrical, Engine · MD

I started my car and after a minute I received a warning saying to check my electrical system and safely pull over. After 5 minutes of trying to drive to the dealership the car suddenly slowed down to a max speed of 27mph and then shortly after slowed to a stop and turned off. The car would not turn on and eventually the 12v battery died. I tried to jump the car but the 12v would not stay charged long enough to put the vehicle into drive. It appears the ICCU is not working and cannot keep the 12v charged to make the car function .

Filed Aug 23, 2024 · Electrical · GA

The recall stated in this report says that it was incomplete, however the recall was completed by the Hyundai Dealership, the software updates were installed and the ICCU failed anyway. When the unit failed the car went into "Turtle Mode", only able to go a max of 25 mph, and the 12 volt battery drained and died.

Filed Apr 29, 2024 · Electrical · WA

12V battery died and vehicle not operable. Luckily vehicle was parked. This has recurred multiple times (3+) Issue has been confirmed by dealer. Not addressed yet. No warning lights of imminent problem

Filed Mar 5, 2024 · Electrical · NJ

12v battery died this morning. The car main battery had 77% state of charge and still the 12v failed. The main battery is supposed to charge 12v as long as it is above 20% state of charge. This seems to be a wide spread problem and Hyundai is not taking any pro active steps in resolving this. All recommended TSB (Technical Service Bulletin) has been applied on the car and car was serviced last week and passed the multipoint inspection.