2025 Hyundai Ioniq 5

The ICCU failed on my 2025 Ioniq 5 within 3 months of ownership and only 811 miles on it. The weather that morning was slightly chilly but not cold. I turned on the car and put it into reverse and after backing up only a couple feet, I heard a pop and the "Check Vehicle Electrical System" message and warning light came on. I had not DC fast charged the car since owning it and had only charged it on level 2 chargers at about 9.6kw to 12kw. The car was not charging the night before the issue occurred and had not been on the charger for several days previously as the battery level was around 70%. There were no issues or symptoms before prior to the failure. The car was towed to the dealership and the ICCU and high voltage were replaced under warranty. This is a major issue with the car and it keeps on happening to eGMP platform cars. The same issue happened with my 2023 Ioniq 5. Hyundai is not providing any information to consumers if they have actually identified the cause of the frequent failures or have manufactured a new part that corrects the manufacturing defect. Please direct Hyundai to issue a statement if they have found a fix or there needs to be a major recall until they identify and correct the underlying problem with the ICCU.

While driving on [XXX] , I heard a 'pop' towards the rear of the car. A dashboard warning appeared notifying me of an electrical fault. The car went into 'limp' mode, which allowed me to drive no faster than around 25 mph. Fortunately, I was within a half mile of my home, so I was able to do a U turn and return home. I called a tow truck, which towed the car to the local Hyundai dealer in Lebanon, NH. This was a Saturday in February, 2026, so dealer inspection did not occur until the following Monday. The dealer confirmed that the problem was a failed ICCU assembly and the associated high voltage fuse. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I was driving on the highway when the car suddenly flashed a “check power supply” warning and then immediately shut down. I was traveling approximately 55 mph when the car came to a sudden stop and I was almost rear-ended as a consequence. I was not rear ended because I had a wide shoulder to immediately pull over onto, but if this had happened in a location without a shoulder, it likely would have caused an accident.

I was driving my vehicle on a freeway with 3 passengers when i heard a muffled pop or thud from behind me. A rear passenger confirmed that it came from beneath the rear seat towards the left side of the car. The vehicle speed immediately dropped to less than 40 mph and a warning message appeared on the dash "Check electric vehicle system". I later noticed a red battery icon appear on the left of the dash. I pulled over after leaving the freeway and attempted to resolve the issue by turning off the car, then restarting it. The notice and red battery icon still appeared. I feel that this sudden reduction in speed is a safety issue because I could have been driving at a higher speed (65-70 vs 45-50). Following cars may not have been able to stop in time, or I cuold have been forced to attempt to get off the road by entering lanes with vehicles travelling at a much faster speed. I was about 5 miles away from home on the start of a 400 mile trip so decided to turn around. Back at home I discovered that a new DTC code had been thrown during or after this event - P1A9096. I transferred to another person's cart to complete the trip, and on return arranged for the car to be transported to a manufacturer recommended dealership to check the issue. The Dealership service department conducted diagnostic tests and determined that the issue was caused by an ICCU failure. The have placed an order for a replacement ICCU unit and fuse. Prior to this event there had been no dash light warnings or trouble codes thrown.

For the HYUNDAI Ioniq 5 XRT, the ICCU, fuse and perhaps hybrid battery malfunctioned. We were in a disabled car on a 4 lane highway with traffic: On February 10, 2026, as we drove out of our home we heard a loud pop. As we got out onto a large 4 lane road near our house, the notice “Check Electrical System” came on and the car’s power was drastically reduced. We made a U turn and drove (20 mph) back to our driveway. We were fortunate that this was mid-day and the road was relatively clear. Normally this is an extremely busy road with traffic moving at 40-50 mph and we would have had great difficulty even pulling out to the side -- as there is only marginal side space on this road. Hyundai has confirmed to us that the ICCU and a related fuse failed. They also think the hybrid battery is also involved and they are testing to confirm that. We had no warning at all -- except for the electrical warning that came on as the car's power was reduced. The car had charged normally and had had no warning signals/signs at all.

COMPONENT FAILURE: The Integrated Charging Control Unit (ICCU) failed on a 2025 Hyundai IONIQ 5 AWD Limited with fewer than 3,000 miles on the odometer. The ICCU controls AC onboard charging and DC-DC power conversion. The vehicle is currently at the dealership and available for inspection upon request. SAFETY RISK: The ICCU failure caused a complete loss of vehicle propulsion, rendering the vehicle fully undriveable. Warning lamps and system fault messages appeared on the instrument cluster prior to full failure. The vehicle lost all ability to be driven or charged. A sudden loss of propulsion in a battery electric vehicle poses significant safety risk to the driver and others on the road. DEALER AND MANUFACTURER CONFIRMATION: The failure was confirmed and inspected by the selling Hyundai dealership. Hyundai Motor America (the manufacturer) reviewed the case and issued a formal written determination in February 2026 concluding the defect was unrepairable, accepting a Lemon Law repurchase under Washington State RCW 19.118. This constitutes manufacturer confirmation that the ICCU failure is a non-repairable defect. WARNING SYMPTOMS: Multiple warning lamps and fault messages appeared on the vehicle’s instrument cluster and infotainment display prior to the vehicle becoming fully undriveable. These warnings preceded the total loss of propulsion. ADDITIONAL NOTE: Despite issuing a written Lemon Law repurchase acceptance in February 2026, Hyundai Motor America has failed to execute the repurchase for over 23 days past document submission, missing their own stated resolution deadline. This complaint is filed to create a federal record of both the ICCU safety defect and HMA’s failure to honor an accepted Lemon Law repurchase in a timely manner.