2023 HYUNDAI IONIQ 5 Complaints

The ICCU in my 2023 Hyundai Ioniq 5 failed unexpectedly, despite the vehicle having completed all applicable recall campaigns intended to address this issue. The failure resulted in a sudden loss of power, with multiple warning messages appearing on the dash (e.g., “Check Electric Vehicle System”) and the inability to drive or charge the vehicle. This posed a serious safety concern as the vehicle became disabled without warning. This issue is known among Ioniq 5 owners and appears to persist even after recall software updates or prior service actions. It raises concerns about the effectiveness of Hyundai’s recall remedies and the reliability of the ICCU hardware itself. The problem poses a potential safety risk due to the loss of propulsion, especially if it were to occur at highway speeds or in high-traffic environments. Requested Action: I urge NHTSA to investigate the continued failure of ICCU units post-recall and whether current recall remedies are adequate to ensure long-term safety and reliability.

The car lost its ability to accelerate during rush hour on a very busy interstate while I was in the far left lane. It started by jerking really hard off and on, like a very hard brake for a second, and then normal for a few seconds, and then hard braking again. I could accelerate after the "braking". There were no warnings or errors. This continued for about a minute while I was trying to decide if it was triggered by accelerating or braking, and I couldn't figure it out. At that point, I couldn't accelerate and received a number of lights and a message to check the EV system or the electrical system. I don't remember because at that point I was trying to immediately figure out how to pull over and not get hit. Luckily, it was slow enough and traffic had just thinned out enough, having passed a popular exit, so that I could coast to the shoulder across all of the traffic. I noticed at this point that the car was in neutral. I couldn't shift into drive, however. I tried to see if turning it off and back on might help. It did at that point. There were no error messages, and I could shift into drive and drive normally after turning it off and back on. Again, I wasn't concerned with documenting an error message that I assumed would be stored. The car is available for inspection. The safety of myself and my kids and other drivers around me was at risk as we could not accelerate and I was in the far left lane to the right of an express lane and left of a lot of traffic to have to cross to get out of traffic. No, the problem has not been reproduced, and it was taken in the next morning to the dealer who found nothing wrong and no stored error codes. No lamps or messages appeared before the loss of acceleration and promptly disappeared after restarting the car. Nothing was stored for the dealer to retrieve, either. The dealer ran diagnostics and found nothing wrong.

I am filing this complaint regarding a serious safety defect in my 2023 Hyundai Ioniq 5 that occurred on 5/14/2025. The vehicle experienced a complete failure of the 12-volt auxiliary battery while parked in my driveway. As a result, the vehicle became fully unresponsive (“bricked”), and I was unable to open the passenger side front door, either of the rear passenger doors, or the back lift door. Only the front driver door could be opened manually and it had been unlocked at the time of the battery failure. I suspect that if I had locked the door prior to the battery failure I would have been locked in the car and I would have had to call for emergency help. This failure posed a significant safety risk, as passengers or I could have been trapped in the vehicle if this had occurred while on the road, in an emergency, or in a remote location. Larger or mobility-impaired passengers would likely be unable to exit safely through the narrow front passenger side if I had been able to open it. Even if I had broken the windows, it is unlikely that larger people could have escaped. There are no mechanical release mechanisms for the doors, and no clear emergency override was functional during this failure. This issue is further exacerbated by the fact that: •The Ioniq 5 relies entirely on the 12V system for door actuation and vehicle wake-up, even when the high-voltage battery is full. •There is no redundancy or mechanical failsafe for opening all doors in a total electrical failure. I have since lift wheel towed the vehicle to the Hyundai of Escondido where the 12V battery was diagnosed as faulty and replaced. The service representative acknowledged other similar occurrences and acknowledged there has been no permanent resolution or acknowledgment of the inherent design risk in such scenarios. This is not an isolated case — numerous owners have reported similar issues across online EV forums and to NHTSA. The lack of emergency door egress is a unexcusable defect.

The ICCU unit failed for the second time. The part is on back order and has not yet shipped, my car has been at the dealership for a month waiting for the part. ICCU failure has been a known issue for some time and the lack of parts to replace is astonishing.

Code P1A9096 Iccu and fuse. The car is currently at a dealer in Barre, VT. While driving numerous warning lights appeared lowering my speed to 10 MPH immediately leaving me vulnerable to a collision in moving traffic. Warning lights include "Check Vehicle Electric System", "Power Limited". Issue confirmed at dealer.

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.

Was driving on highway and started receiving error messages for "check electrical system". Car speed dropped to max of 45mph while actively on a highway. Was able to pull off an exit but car needed a 55 mile tow to the closest dealer. Dealer has identified that the ICCU needs to be replaced but has no timeline as the item is on back order. Car is model year 2023, purchased in February of 2023 and has 22,000 miles on it.

ICCU failed for a second time and needed to be replaced. This happened within 24 hours of the initial replacement. There is a major problem with this part. Car was parked in my garage charging when the failure occured.

One month ago, my car experienced an failure and the warnings on the dash reported to check the electrical supply and then to stop driving the car immediately. I had it towed to a dealership who reported the ICCU failed and it'd take 1-2 weeks to get replacement parts and repair. A month later, I was just told the part is on indefinite back-order and they have no ETA when a replacement part will be available. Hyundai is selling an unsafe vehicle without that can die on the road and have no way to fix the issue. Google "Hyundai ICCU failure" and you'll see this is a systemic problem and Hyundai is doing nothing to fix these issues and is putting out 2025 models that are dying on the road with no solution.

Vehicle suddenly lost power. Towed to Hyundai dealer. Diagnosed as ICCU failure.