2023 HYUNDAI IONIQ 5 Complaints

My Ioniq 5 has encountered the renowned "ICCU" failure -- 35k miles in, 2.5-3yrs of ownership. I had a loud 'pop' noise behind my driver seat occur and then my vehicle went into limp mode. The ICCU failure is confirmed by the dealer, but the part is on massive backorder nationwide...

My electric car lost power while driving with no warning. It came to a stop in the middle of the road and a message came on the screen that said "Stop vehicle and check power supply". There was no advanced warning and I had to have the vehicle towed to the dealer. Upon inspection by the dealer I was told the ICCU unit failed and needed to be replaced. The dealer stated the the part was on backorder and there was no ETA for the part. Thankfully I was not driving on the freeway or I may not have been able to get the car to the shoulder. It was a very scary thing to lose all power in the middle of the road.

1. What component or system failed or malfunctioned, and is it available for inspection upon request? The electric vehicle system appears to have failed, preventing the car from starting and staying on. Even after attempting to jump the 12V battery, the vehicle would briefly turn on and then immediately shut off. This issue was previously confirmed by the dealer about four months ago, and they supposedly fixed it. However, it has now happened again, leaving the car completely inoperable for the second time. The vehicle is available for inspection upon request. 2. How was your safety or the safety of others put at risk? This failure left me completely without transportation for the second time, which is a serious reliability and safety concern. If this had occurred in traffic or in an emergency situation, it could have posed a major risk, as the vehicle is unable to move at all. Additionally, because this issue has recurred despite prior repairs, it raises concerns about the reliability of the vehicle’s electrical or power management system and the effectiveness of past fixes. 3. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, the problem was previously confirmed by the dealer about four months ago, and they claimed to have fixed it. However, the issue has returned, meaning the original repair did not fully resolve the problem. At this time, it has not yet been re-inspected for the second occurrence. 4. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? The dealer inspected the vehicle during the first occurrence four months ago. However, for this second occurrence, it has not yet been inspected by the manufacturer, police, insurance representatives, or other authorities. 5. Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? Yes, multiple warning messages and symbols appeared on the da

These cars had an open campaign earlier in the year to check for faulty ICCUs. Mine was check in Jan and deemed to be good. In early Feb I was driving home alone late at night and suddenly I was unable to go faster than 20mph and in a matter of minutes the car shut off. It had to be towed and the dealer informed me the ICCU failed. It was very scary and extremely dangerous. This has been happening so often with the Ioniq 5's and there should be a mass recall.

Used the remote climate start which was working when I went out to the car. The car let me in; but would not respond to start until finally the dash lit up with a lot of electrical system warning lights. The dash then went dark and the car would not respond. I was locked out and had to use the physical key to reenter the car when I got out to check to see if the lights were on. I had it towed to the dealer where an ICCU failure was diagnosed. The replacement ICCU is on back order with no ETA. They do not have any loaners available and Hyundai Corporate customer service has been giving me delays refusing to say if they will reimburse me for a rental. Had previously done all the software updates and inspections at the dealer for the recalls for the ICCU.

The car was parked and off. I turned the car on. It started normally. Just before shifting to reverse to leave, I hear a loud "pop" sound from under the rear seat area. A yellow "check electric vehicle system" warning appears on the dashboard, with a battery warning icon. About 30 seconds later, a red "stop vehicle and check power supply" warning appears with an alarm/chime. I have completed all ICCU recalls and any other recalls on the vehicle. I had just dropped my son off for a preschool trip. I am grateful I was not driving with him when this happened as the car becomes inoperable.

On March 15, I pulled my car into a charging station and turned it off. The charger would not recognize my car, so I figured I'd pull into a different charger. However, when I tried to start my car to move it I got the dreaded Low Voltage warning. The car would not start, and even when a tow truck brought a 12V charger it would not jump. It was completely dead. It had to be dragged with chains onto a tow truck. It was brought to a dealer where it has been ever since. I have just been informed by Hyundai corporate that the car needs a new ICCU but that they are backordered. This is the SECOND ICCU issue I have had with this car. The first was on December 26 when the issue was a recall [that I had not been made ware of yet] for a software update. I believe a fuse and the 12V battery were also replaced as the 12V completely discharged from the failure. On this occasion, the vehicle was dead in my driveway. I consider myself fortunate that the car did not die on a highway or while I was actually driving it, because that is very dangerous. But this car is not reliable and I feel like Hyundai should be buying back the lease and putting me into a different vehicle.

The contact owns a 2023 Hyundai Ioniq 5. The contact stated that the recall repairs for NHTSA Campaign Number: 24V868000 (Electrical System) and 24V204000 (Electrical System) were completed; however, the repairs failed to prevent a failure from occurring shortly afterwards. The contact stated that while attempting the charge the hybrid battery, the vehicle failed to charge to full capacity as intended. In addition, the contact was alerted by the vehicle with a Voice message that the vehicle had failed to charge as intended. No warning lights were illuminated. The vehicle was taken back to the same local dealer where it was reprogrammed; however, the failure reoccurred. The contact was advised that the ICCU needed to be replaced; however, parts were not available. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 16,307.

On March 20, 2025, my 2023 Hyundai Ioniq 5 displayed the error "Stop check vehicle power supply" and abruptly shut down during rush-hour traffic, leaving my young son and me stranded on a heavily congested bridge. Immediately, the car’s display went dark, doors wouldn't unlock, and the gear shifter was immobilized. With no emergency functions available, we were completely trapped. On a slight incline, I had to continuously hold the brake pedal to prevent rolling forward into increasingly aggressive traffic, making an already frightening situation terrifying for my child. Police arrived but struggled to assist preventing the car from moving. After several tense minutes, the dashboard briefly flickered back on, enabling me to unlock the doors. AAA identified a dead 12V battery, replaced it at my expense, but the critical error persisted, causing another complete shutdown shortly thereafter. The vehicle was towed to Hyundai of Bedford, where technicians diagnosed the issue as a failed ICCU and fuse, parts that are now backordered due to high number of vehicals having this same issue. Alarmingly, Hyundai plans to replace these faulty parts with identical models, despite my vehicle having completed all recall updates. This means the dangerous malfunction could occur again without warning, posing ongoing severe safety risks to my child, myself and those around use. This deeply traumatic event exposed critical vulnerabilities in the Hyundai Ioniq 5, especially dangerous for families, elderly drivers, or anyone caught in similar emergencies. The absence of functional basic safety measures left my son and me unnecessarily vulnerable. My trust in this vehicle and any thing using the same ICCU is permanently broken. Hyundai urgently needs reliable, redundant safety systems to prevent such life-threatening scenarios. Until then, we cannot feel safe or secure in these vehicles.

After all of recall software updates were applied the ICCU still failed with no warning beforehand and resulted in power and propulsion failure.