Mar 27, 2026Electrical system
ICCU and its fuse blew randomly while reversing out of a parking spot. A warning light appeared on the dashboard saying "check electric vehicle system" after a loud pop noise came from the rear passenger side. The ICCU charges the 12V battery on board, and when the 12V dies the whole car dies, resulting in the car shutting down suddenly. It's a known issue with this model car. The service center confirmed the ICCU blew when they ran diagnostics.
NHTSA ODI 11727506
Mar 27, 2026Transmission & drivetrainElectrical system
ICCU failure. Common problem but Hyundai seems to have no fix despite it happening for years now.
NHTSA ODI 11727550
Mar 27, 2026Electrical system
Based on all symptoms - loud pop followed by limp mode and electrical warning, and inability to charge -- iccu is busted.
NHTSA ODI 11727611
Mar 26, 2026Electrical system
I was driving at 25 mph when I heard a loud pop come from the rear of the car and subsequent warning message came up on the dashboard - "STOP VEHICLE AND CHECK POWER SUPPLY". In an electric vehicle this is a very alarming message to see. I was fortunate to be close to home so I was able to drive home and call roadside assistance for my car to be towed to the dealer. The vehicle has since been diagnosed with an "ICCU" failure. I had no indication or warning that this was going to happen, just a sudden failure.
NHTSA ODI 11727361
Mar 21, 2026Electrical system
I was driving in a parking lot and heard a “pop” sound like a balloon breaking. The Ionic 5 lurched and stopped. A red circle appeared on the dash and said “check electrical system.” I slowly maneuvered the car into a parking spot because there was very little power and turned off the car. I called the Hyundai dealer and they told me to have the car towed to the dealer in Palm Springs, CA. When the tow truck unloaded the Ionic 5 at the dealer, I attempted to move the car into a parking spot so it was out of the traffic lane. I started the car again it again lurched and a yellow circle came up with a turtle icon. Then another red circle appeared “check 12V battery”. The car would not move after that. I went into the Hyundai service department and talked to the service representative. He said he would take the vehicle in for service and I signed the paperwork.
NHTSA ODI 11726091
Mar 20, 2026Electrical system
Pop sound while driving. Lost ability to drive at normal speed. Was able to take car to repair shop and was informed of ICCU failure
NHTSA ODI 11725754
Mar 20, 2026Transmission & drivetrainElectrical system
Received multiple "Check Vehicle Electric Systems" on a drive which went away and then got into the car, turned it on, shifted into drive, and heard a pop from bellow before moving at all and the car went into Turtle Mode and blasted warnings. The car completely died with zero power leaving it stranded in sub freezing temperatures and unable to lock the car or open the lift gate to access the trunk area. Eventually it was towed to the dealership and was diagnosed to have a faulty ICCU which took 5 weeks to replace.
NHTSA ODI 11725845
Mar 20, 2026Electrical system
ICCU failure while driving.
NHTSA ODI 11725950
Mar 19, 2026Electrical systemEngineFuel system
I was driving and the car gave an electrical system warning, slowed, and thereafter would not go above about 20mph. Fortunately this happened on a local, low speed limit street. I'd rather not think about what might have happened if this had happened on a highway. The Integrated Charging Control Unit (ICCU) is no longer working as it should. The problem has been confirmed by the dealer/manufacturer service station.
NHTSA ODI 11725530
Mar 19, 2026Fuel system
Loss of power leaving driver stranded
NHTSA ODI 11725547
Mar 19, 2026Electrical system
ICCU Failure. Vehicle underwent deal TSB for ICCU failure resolution prior to still failing months later.
NHTSA ODI 11725581
Mar 19, 2026Engine
The vehicle experienced a sudden failure of the 12V battery while on the road. The car stopped completely and became inoperable. At the time of failure, there were no tail lights or proper warning indicators working, which created a very dangerous situation, especially in traffic. I was stuck on the road for about one hour waiting for a tow truck. During that time, other vehicles were honking and passing by, increasing the risk of an accident. The vehicle had to be jump-started before it could be moved. Details: What component failed: The 12V battery system failed unexpectedly. The vehicle is available for inspection upon request. Safety risk: Loss of power caused the vehicle to stop on the road with no tail lights, putting my safety and others at serious risk. Reproduction/confirmation: Issue was temporarily resolved with a jump-start, but this is a known issue reported by other owners as well. Inspection: The vehicle has not yet been inspected by the manufacturer or dealer after this incident. Warnings/symptoms: There were no clear warning lights or messages before the failure. The issue happened suddenly without notice.
NHTSA ODI 11725650
Mar 19, 2026Electrical system
ICCU failure
NHTSA ODI 11725713
Mar 18, 2026
ICCU went bad. Battery warning light appeared a few hours before Vehicle stopped. Vehicle was inoperable and needed to be towed.
NHTSA ODI 11725139
Mar 18, 2026Transmission & drivetrainElectrical systemEngine
While driving I received the infamous "Stop vehicle and check power supply" warning, and it was then inoperable, needed a tow to the dealer for ICCU replacement. I can't believe you terminated your initial investigation into this in 2023 because they did a recall (which my car received). That recall did not fix the issue. It is March 2026 and Ioniq 5 and other models with the same electric system are dying on the road at the same rate as before. There is a large percentage of failed cars, and every failure is dangerous. This is a huge safety issue, and is not receiving adequate oversight by the NHTSA.
NHTSA ODI 11725342
Mar 17, 2026Transmission & drivetrainEngineFuel system
I was merging onto the highway. I got a warning that I needed to check my electrical system. I was able to back down the highway ramp and park on a side street. Within 20 minutes the car was fully dead and AAA needed to tow it to the dealer. The dealer confirmed that the ICCU needs a replacement. My family is lucky this happened in a place we could safely get to a side street. Had it happened 5 minutes later we would have been stranded on the highway with 2 small children.
NHTSA ODI 11724910
Mar 17, 2026Electrical system
ICCU failure happened for the second time. Car stopped randomly with no Power. Very dangerous, this is a known issue for years now and Hyundai is not doing anything about it.
NHTSA ODI 11725056
Mar 14, 2026
Diagnosed ICCU Failure. Complete loss of power, went into "turtle mode," then told to stop car immediately and have it towed to the dealership. Vehicle diagnosed several days later as having an ICCU Failure.
NHTSA ODI 11724295
Mar 10, 2026Electrical system
Vehicle Details: 2024 Hyundai Ioniq (leased from McGovern Hyundai, Wilmington) Recall Services Notes: ICCU S/W,DTC CHK,&FUSE/REP([XXX]) • 272 Mileage: 10,714 mi Owner: [XXX] What Happened ([XXX]): My Ioniq suddenly died in the center lane on [XXX] near CVS Market, Burlington MA This created a dangerous nighttime traffic jam, The dashboard showed "12V battery voltage low. Stop safely" - the exact same issue fixed last year under recall. Key Details from McGovern Hyundai, Advisor said"100 emergencies waiting" - yet they're still actively selling new cars without capacity to service them? The 2024 car (within warranty) has been in the workshop for past 1 month. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA ODI 11723195
Mar 5, 2026Electrical systemSpeed controlFuel system
While driving northbound on US-280 freeway, the vehicle experienced sudden deceleration with maximum speed limited to approximately 40 mph. The dashboard displayed a "Check Power Supply" warning. The vehicle required a tow to the dealership. Dealer diagnosis indicates likely ICCU (Integrated Charging Control Unit) failure. This is a known issue affecting multiple Hyundai Ioniq 5 vehicles, with numerous consumer reports of the same failure mode. The sudden loss of propulsion at highway speed created a significant safety hazard though we were able to make it off the freeway with hazards on. However shortly after exiting the vehicle further slowed and eventually died on the side of the road as did the hazard signals.
NHTSA ODI 11722142
Mar 4, 2026Transmission & drivetrain
According to Hyundai, all active recall campaigns have been addressed on this vehicle (NHTSA site says it wasn't, Hyundai claims it was on 9/22/2025). Last night (3/3/2026) while driving on an unlit, two-lane country road about 20 minutes from my house, I heard and felt a bang noise from underneath the rear cabin of the car accompanied by a message stating "Stop vehicle and check power supply" on the dash. The car immediately went into a limp mode, reducing speed to ~40mph. After about 0.5 miles, the car further reduced speed to about 25mph (in a 55mph zone). As speed reduced further (no indication of what the speed would be reduced to), I pulled the car off of the road and awaited tow service. As this happened in the evening on an unlit country road, I was forced to wait for assistance along a stretch of road that could have been hazardous. Hyundai's claimed recall campaign work was performed on 9/22/25 with subsequent recurring failure about 5 months later. The dealer cannot confirm the diagnosis or offer estimates of repair time/availability until they see the car (currently scheduled for next week).
NHTSA ODI 11722069
Mar 3, 2026Electrical system
Car was acting normally. Suddenly, the car would not accelerate. I was on a small road with no place to pull over. Vehicle said to pull over check electrical system. At great risk to my life and the safety of my children, we managed to get to a safe spot before the entire vehicle shut down. We expect that this was a failed ICCU.
NHTSA ODI 11721849
Feb 28, 2026Electrical system
- What component or system failed or malfunctioned, and is it available for inspection upon request? The ICCU failed. It is not available for inspection. - How was your safety or the safety of others put at risk? Minimally. The car alerted me that it was power-limited and that I should stop the car immediate and get it towed to the dealer. - Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. - Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, the dealer. - Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Yes. The car informed me it was power limited when I started it. When I started driving after about a mile I was instructed to pull over get a tow.
NHTSA ODI 11721169
Feb 27, 2026Electrical systemFuel system
On January 31st, 2026, not long after starting a journey in my car, I got a “check electrical systems” warning. I was close to home so was able to turn around and drive home. Just before pulling into the driveway, the warning changed to a “power limited” warning. On Monday Feb 2nd, I had the car towed to my local dealership, where it has been since. The dealer confirmed that it was an issue with the ICCU component which is on back order to this day.
NHTSA ODI 11721005
Feb 27, 2026Electrical system
Car suddenly out of the blue reported electrical system problem and battery problem. It also entered turtle mode where it would not go more than 10 MPH. If accelerating across an intersection this would have been extremely problematic if expecting to be able to travel faster than that. Towed to dealer that said it is a failed ICCU. This is a common failure mode and there needs to be a fix and safety recall for this.
NHTSA ODI 11721033