2025 Hyundai Ioniq 5 problems

“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.”

“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 is still sitting waiting to be looked at (2 hours away from where I live)”

“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. Photos of the instrument cluster are attached. I consider a sudden loss of drive power at 4,368 miles to be a safety-related defect, and I have reported it to NHTSA. My situation: This is one of two vehicles in our household, and both of us need to get to work. The dealer is about 30 miles from my home. I am without transportation as of September 19. What I am requesting: 1. Written authorization for a rental vehicle starting immediately and continuing until my vehicle is…”

“When I use the adaptive cruise control and use the lane keeping assistance the system keeps giving me an error message that I'm not looking at the road. I believe this is a known problem and Hyundai pushed an software fix TSB 25-G1-16H in November 2025. My car appears to have the update but still repeatedly gives me the same error message. It's very distracting and since the error message flashes on dash where you usually see the camera monitoring right side of car that feature is impaired. I have had at dealership twice and while the technician knows its an issue there's nothing they can do without Hyundai's decision to correctly fix with software update. I am over 6' tall and where glasses, two things I can't change.”

“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.”

“The driver attention warning feature is defective and often requires you to take your eyes off the road and stare at the DAW sensor in order to eliminate the car's constant "attention" warnings. Even while looking straight ahead while driving, the DAW is often erroneous and will disengage safety features (e.g., lane keeping assist, adaptive cruise control, etc.) because the DAW erroneously thinks that the driver is not paying attention. As another example, if you are driving uphill/downhill or on a curved road and are looking at the road ahead of you at a slight angle, the DAW will erroneously report that the driver isn't paying attention. The system will then disable the cruise control and lane keeping assist, creating a hazardous situation. Alternatively, the driver can look DOWN (not looking at the road) at the DAW sensor and stare at it until the car reacts. This takes your eyes off of the road and creates hazardous situations. As someone who wears prescription glasses, the problem is even worse. I cannot set a comfortable seat/steering wheel configuration where the DAW can "see" through my prescription glasses. If I want to drive in my normal position, I…”