*Median odometer reading when the problem happened, where owners gave one. One complaint can name several problem areas.
Electrical system
Second failure of the Integrated Charging Control Unit (ICCU) on this 2025 IONIQ 5. The ICCU stopped charging the 12-volt battery, leaving the vehicle unable to start. This is the second time the ICCU has failed and required replacement in approximately one year. The vehicle was towed to the dealer. ICCU failure can cause a loss of drive power while driving; this failure was discovered while parked. Earlier model years (2022-2024 IONIQ 5) are covered by recall 24V-868 for this same defect; this 2025 vehicle is outside that recall population and has now failed twice.
Oct 26, 2026Electrical system
On XXX, while driving my 2025 Hyundai Ioniq 5 on a local road, the vehicle suddenly lost power and would not accelerate beyond 40 MPH. There was no prior warning. I had not yet merged onto the expressway. Had this happened at highway speed, I would have been unable to keep up with traffic, which would have created a serious risk of a collision. I continued driving at reduced speed until I could safely pull into a gas station. Once stopped, the instrument cluster displayed "Stop vehicle and check power supply." About 10 minutes later, with the vehicle parked and still on, it displayed "Check 12V battery. Stop safely and engage parking brake." Roughly 10-15 minutes after that, the vehicle…
Oct 10, 2026Service brakesCrash
I am reporting a serious suspected brake malfunction involving my 2025 Hyundai IONIQ 5, VIN [XXX]. While driving straight on a wet road during rainy conditions, I pressed the brake pedal to slow down. The pedal felt soft and sank toward the floor, but the vehicle did not slow down or respond as expected. The vehicle continued moving, and an accident occurred. The vehicle sustained major damage and may be a total loss. I am concerned that the braking system may have malfunctioned. I am requesting that NHTSA review this incident for a possible safety-related defect affecting the braking system of the 2025 Hyundai IONIQ 5. I request that this complaint be considered alongside other reports of…
Oct 10, 2026Power train
I am writing to document my case regarding my leased 2025 Hyundai Ioniq 5 XRT. Vehicle: 2025 Ioniq 5 XRT, VIN [XXX] Lease start / delivery date: Odometer: 4,368 miles Servicing dealer: Stevinson Hyundai, [XXX] Case number: XXX What happened: On Saturday, XXX, while I was driving, the vehicle displayed "Stop vehicle and check power supply" with the red 12V battery warning and the master warning light, and power was limited to approximately 25 mph. The high-voltage battery was at 66 percent. I was able to get the vehicle home at reduced speed, and Hyundai Roadside Assistance towed it to the dealer the same day. The symptoms are consistent with an ICCU failure, pending the dealer's diagnosis.…
Sep 19, 2026Steering
Driving at highway speeds, the front end feels unstable. It feels as if the tires are jumping around and will move the car to the right or left. It is difficult to maintain control. I had it into the dealer shortly after I bought the car to complain about what I thought was a front end alignment problem. They didn't think there was an issue until they got it into the shop. They said afterwords that it WAS OUT OF LINE. But their fix did not hold, so I went in again for the one year maintenace and mentioned the problem, but they said it was not out of line. Well, The problem still exists. Something serious is wrong and needs to be fixed.
May 1, 2025Electrical system
Full electrical power system failure. Heard a loud pop noise emanating from under the rear seats of the car. The power. Failure lights came on and the car lost power. We were able to get the car to slowly drive back to the garage where it completely shut down and was inoperable from that point on. Car has been towed to the local dealer for diagnostics and repair.
Sep 8, 2026Electrical system
On 8/30 my vehicle experienced a power loss on a highway (reported here separately). I took the car to the dealership and they could not replicate the error and gave the vehicle back to me on 9/4. Later that day I had to drive 2 hours north to a wedding in the mountains. At 9:30pm my vehicle experienced a full drive power loss on an unlighted, curving, rural 2-lane mountain road in an area with minimal cell phone service. I tried to restart the vehicle several times and could not get any power. I called roadside assistance and had to wait over 2 hours in the dark on a winding mountain road for the tow truck to find us and then be towed 40 minutes away to the nearest dealership where my car…
Sep 4, 2026Fuel/propulsion system
Driving home near my apartment, I had to join a busy highway from a full stop. I found a small gap and tried to accelerate to quickly merge into traffic, when my car made a high pitched alert noise and noticably did not accelerate beyond about 25 miles per hour on a 45-50mph highway with heavy traffic. I turned on my hazards and still ended up with a line up of cars honking behind me. Flooring the accelerator did absolutely nothing to increase my speed. On slight downhills I could get up to about 40mph but as soon as it leveled off my speed went back down to limping along. I was able to exit the highway at slow speed and tried to parallel park in an avaialble spot but could not reverse. I…
Aug 30, 2026
Owner complaints are submitted to NHTSA by the public and are not verified. Shown as filed (NHTSA removes personal details); long reports are shortened.