2025 HYUNDAI IONIQ 5 Power Train Problems

I am reporting a serious safety defect involving my 2025 Hyundai Ioniq 5 (lease vehicle, brand new). While driving on a highway in Massachusetts during snowy conditions, the vehicle suddenly displayed a critical warning message “Stop and Check Power Supply” and lost power, forcing us to stop on the highway. There were two children in the vehicle, and the situation was life-threatening due to traffic speed, weather conditions, and lack of a safe shoulder. The vehicle is new and under lease, and this type of failure is unacceptable and extremely dangerous. The car had to be towed to Hyundai of Braintree, MA. This is a serious safety failure, not a comfort or convenience issue. I am concerned this defect could result in serious injury or death if it happens again, either to my family or to others. I am requesting a formal investigation into this defect.

I was driving on the freeway in the left lane when suddenly a bunch of error lights popped up on the dash and the car threw itself into neutral. When I tried to give the car acceleration it wouldn’t go which is when I realized the car was in neutral. When I tried to go into drive it did not go so I turned the hazard lights on. Turned off the car, turned it back on and then again all the error lights popped up. I went into drive and when I drove a loud bang noise happened in the rear and after a few feet the car went into neutral. I repeated the process trying to merge from the left lane into the middle where finally the car would not even go into drive anymore. I then called 911 and had them tow the car off the freeway while I waited inside. Car had 3400 miles, was only a few months old (brand new) and I had 60% battery left with almost 200 miles of electric range left. It was a sunny day with no moisture recently.

The ICCU unit failed causing the car to first have low power, reducing the maximum vehicle speed to 25 MPH, then causing the 12V battery to lose charge making the car inopperable.

On the afternoon of Saturday, December 12th 2025 I was preparing my car for a trip an hour north and back to drop my daughter off with her grandmother. I was charging my car with my Level 2 charger and preheating my car. Upon leaving for the trip, within a half mile I heard a loud popping sound coming from the rear of the vehicle and immediately had a warning on the vehicle stating "Stop Vehicle and Check Power Supply". The vehicle soon started to lose drive power, and I had to perform a U-turn and then parked at the nearby Quaill Volunteer Fire Department to perform a basic safety check. Knowing that I probably had the Hyundai Ioniq 5 ICCU issue, I knew that my car would soon have no power so I waited for an opportune time to leave the fire station to coast back to my house. After arriving home, I contacted Hyundai Roadside Assistance and my car was soon towed away. I was extremely fortunate to be so close to home when this happened - from what I know of the issue, had we been stranded on the highway with this issue we would likely not have been able to use the HVAC systems in the vehicle for long. At this point, the issue has been diagnosed at the dealership as an ICCU issue which is covered by warranty. I have not been told to modify anything about my charging amperage, and there has been no admission that the ICCU part itself is faulty (though I believe it must be - my vehicle has less than 8,000 miles and the previous model years of Ioniq 5 all had ICCU recalls already.)

I was leaving from a friends' house and got a "Check electric vehicle system" error and the car went into "limp" mode while on the road. I drove to a hotel parking lot and dropped off my family then proceeded the next day to drive the car to a local dealership for service and the car maxed out at 12 mph before crawling to 1 mph while going up a hill before I could find a place on the side of the road to stop. While awaiting a tow truck the car's electrical system fully "died" leaving me stranded on the side of the road without even hazard lights to warn surrounding traffic. The problem has not yet been evaluated by a dealership, manufacturer or any other agencies. Several warning lamps and messages appeared, including the "Check electric vehicle system" error message.

My car worked to get to an appointment on 22 Nov. It flashed an error 2 minutes into a 20 minute return trip, saying the cars propulsion failure was imminent. Vehicle would not turn back on after the 3 mile drive home. The ICCU failed. If this failed while driving, or while I was in a hot/cold location, my life and those around me would have been at risk. The dealer has been working with Hyundai America for a month to fix the vehicle, and so far has not been able to after trying 2x replacement parts.

The ICCU (Integrated Charge Control Unit) failed. Fortunately I was in a parking lot at the time, as the vehicle limited its top speed to around 25 mph. Had the failure occurred on a highway it could have caused a collision. While this is a 2025 model year Ioniq 5, the ICCU hardware (part 36400-1XAA0) remains unchanged across all Hyundai/Kia/Gensis vehicles sharing the eGMP platform. NHTSA previously issued recall 24V-868 intended to address such ICCU failures. While the modified software is included from the factory in the 2025 model year Ioniq 5, it appears that the 24V-868 recall is not a complete fix. Indeed, ICCU failure continues to be one of the most commonly reported owner issues, both for vehicles which have already had the “fix” from recall 24V-868 and for newer vehicles outside of the recall’s scope. This can be confirmed from the numerous posts and videos online (YouTube, Reddit, Ioniq forums, etc.). Given that ICCUs continue to fail at a significant rate, resulting in reduced vehicle speed and vehicle shutdown within minutes (as soon as the 12 V battery is exhausted), I strongly urge NHTSA to do the following: 1. Consider the current ICCU software update to be an ineffective remedy for recall 24V-868. 2. Broaden the scope of recall 24V-868 or create a new recall for all Hyundai/Kia/Genesis eGMP platform vehicles to address this defect. 3. Require that Hyundai/Kia/Genesis create and deploy a truly effective remedy for this defect.

EV battery failure. This is a known issue that Hyundai is refusing to acknowledge is a common problem on their cars.

Was driving for 12 miles, at a stop light. Light turns green, I accelerate, loud collision warning goes off and warning “battery overheated! Pull over safely and leave the vehicle”. Could not pull over safely because the car immediately ceased and locked up, car behind me nearly rear ended me and swerved to avoid. Is this another ICCU unit failure? Car towed to dealership (car has 2056 miles in it, it’s practically new) and been there for almost a month now with no repairs done and still diagnosing the problem. This car is unsafe.

On the first snowy day of the year, the car experienced an apparent ICCU failure. Loud pop followed by warning lights, reduced power and eventual complete shutdown of the car. Car has been towed to dealership for diagnosis and repair.

I heard a "pop" and then immediately saw "check electric vehicle system". The code I'm receiving in the app is P1A9096. The car was limited in driving speed, and I managed to get the car to the dealer before it stopped driving completely. I have about 8000 miles on this <1 year old car, and it seems like the ICCU has fried. Hyundai says this is under 1% of all cars, but from the internet it seems like this happens way more frequently. Reporting to the NHTSA so that there's record of this happening, given the frequency it seems to happen on the internet and the paucity of solutions (beyond putting in another faulty part) from Hyundai.

Vehicle will hesitate/shudder and pulsate at highway speeds. Between 57mph and 78mph seems to be where I can feel it the most. This happens on all drive modes and with or without brake regeneration turned on or off. Nothing seems to make it worse or better. Here is an example. If you are driving 65mph on the highway and holding your speed steady, the car motor feels like it's cutting in and out. Juddering forward and back. If you accelerate a tiny bit, it gets ever worse. It feels almost like the input signal from the peddle is choppy, causing the car motor to judder. It is a forward to back motion. Not a vibrate or side to side motion. I took the car to the dealership where they confirmed they could feel it too. They ended up rotating my tires... Said that's all they can really do because Hyundai doesn't have anymore information. They basically said sorry but they can't help.

I leased a 2025 Hyundai Ioniq 5 with the exact same issue. The VIN is [XXX] My new Hyundai Ioniq 5 is having the same problem again! Vehicle will hesitate/shudder and pulsate at highway speeds. Between 57mph and 78mph seems to be where I can feel it the most. This happens on all drive modes and with or without brake regeneration turned on or off. Nothing seems to make it worse or better. Here is an example. If you are driving 65mph on the highway and holding your speed steady, the car motor feels like it's cutting in and out. Juddering forward and back. If you accelerate a tiny bit, it gets ever worse. It feels almost like the input signal from the peddle is choppy, causing the car motor to judder. It is a forward to back motion. Not a vibrate or side to side motion. Dealership said basically they'll keep the car and possibly we can hope Hyundai will lemon law me out of the car. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)