2025 Hyundai Ioniq 5

The ICCU (integrated charging control unit) failed July 6, 2025 when the car had 6,800 miles on it. I was driving it on the road at the time and it suddenly would not go faster than 20 miles per hour. It was in the shop for weeks to repair. The replacement ICCU just failed again on January 31, 2026 at a mileage of 15,380. The car is inoperable and cannot be driven.

The Integrated Charging Control Unit in our 2025 Ioniq 5 failed on vehicle startup. Fortunately the vehicle was parked when the part failed. There were no issues or symptoms prior to the failure and subsequent fault message. Failure of the ICCU has been confirmed by our local Hyundai dealer which is now in possession of the vehicle awaiting repair.

The Integrated Charging Control Unit (ICCU) component of the 2025 Hyundai Ionic 5 with less than 6 months and 5,081 miles of driving failed. This failure was noted by the warning systems in the car indicating car needed to be stopped and not driven. (Photo attached in later section) Further information indicated a very limited distance to drive before complete car shutdown late at night. The ICCU component failure has been confirmed by the dealership service department where the car was purchased. No warnings were noted before the ICCU failure. This ICCU component failure seems to be common enough to be a known failure, but the frequency has not been made public.

Backing out of a parking space, I heard a loud pop sound from the back of the cabin. A electrical warning showed in the dash to check the charging system. The vehicle was limited to 22 mph and I limped home. Just short of getting home, a warning alert sounded and the dash displayed an alert to stop the vehicle and park. Vehicle was towed to the dealer, who diagnosed it as an ICCU failure.

While driving at normal city speeds, the vehicle suddenly displayed a warning message stating “Stop vehicle and check power supply,” accompanied by a red battery warning indicator. Shortly after the warning appeared, the vehicle entered a reduced-power or “limp” mode, with severely limited acceleration and speed. This created a safety concern as the vehicle could not maintain normal traffic flow. The high-voltage traction battery state of charge was normal at the time, indicating the issue was not related to battery depletion. Prior to the failure, there were no unusual driving conditions, accidents, or modifications to the vehicle. Ambient temperature was cool but within normal operating conditions. Due to the loss of power and safety risk, the vehicle was not driven further and was towed to an authorized Hyundai dealership for inspection. The problem was confirmed by the dealer, who diagnosed a failure of the Integrated Charging Control Unit (ICCU), which manages charging and power conversion between the high-voltage system and the 12-volt electrical system. The dealer determined that the ICCU requires full replacement. The vehicle remains at the dealership awaiting parts and is available for inspection. The failure resulted in sudden loss of drivability without prior meaningful warning, posing a potential hazard to the driver and surrounding traffic.

On Friday evening, my 2025 Hyundai Ioniq 5 was parked at a ferry terminal in central NJ in cold (~32°F), windy conditions near water. At approximately 6:20pm, I remotely activated climate control using the MyHyundai app. When I entered the vehicle around 6:25pm and attempted to start it, the dashboard immediately displayed “Stop vehicle and check power supply” and “Check electrical vehicle system.” The MyHyundai app reported diagnostic code PIA9096, which is widely reported by other owners as an ICCU failure. The vehicle became completely inoperable, could not be shifted into neutral, and could not be jump-started. I attempted boosting the 12V battery and AAA also attempted, with no success. Both AAA and Hyundai Roadside Assistance refused to tow the vehicle because it could not be placed in neutral, leaving me stranded in freezing conditions and forced to abandon the vehicle overnight in a public lot. The following morning, I installed a brand new 12V battery, which allowed the vehicle to power on, but the same electrical errors remained. The vehicle was then towed to a Hyundai dealer. After several days, the dealer confirmed diagnostic codes PIA961C, PIA9096, and P056216 and diagnosed failure of the ICCU and high-voltage fuse. The dealer ordered ICCU assembly 36400-1XAD5 and high voltage fuse 375F2-GI040. The dealer cannot provide any ETA for parts and stated the vehicle will be inoperable until repaired. I am informed by many other owners that multi-week or multi-month delays are common for this same failure nationwide. This failure resulted in a sudden, total loss of vehicle function, left me stranded in unsafe conditions, and made the vehicle impossible to move or tow normally. This appears to be a known, systemic defect affecting Hyundai EVs across multiple model years. Vehicle is currently at Hyundai dealer and available for inspection.

While driving, all of a sudden I got a "Stop vehicle and check power supply" message on my dash and the car slowed down. I could not accelerate. It was dangerous as I was driving during commute time. I had the car towed to the nearest Hyundai dealership. The car completely died (no power) while parked at the dealer parking lot. After diagnosing the car, the technician said it was an ICCU failure.