2025 HYUNDAI IONIQ 5 Complaints

After hearing a sudden loud pop, my car lost all power. I was able to pull to the side of a busy 2 lane road. It was dangerous and scary to be stranded alone on a very busy road. The car had to be towed to the dealership. It took 48 days to replace the ICCU, fuses and the coolant. The service manager said this is a known issue.

COMPONENT FAILURE: The Integrated Charging Control Unit (ICCU) failed on a 2025 Hyundai IONIQ 5 AWD Limited with fewer than 3,000 miles on the odometer. The ICCU controls AC onboard charging and DC-DC power conversion. The vehicle is currently at the dealership and available for inspection upon request. SAFETY RISK: The ICCU failure caused a complete loss of vehicle propulsion, rendering the vehicle fully undriveable. Warning lamps and system fault messages appeared on the instrument cluster prior to full failure. The vehicle lost all ability to be driven or charged. A sudden loss of propulsion in a battery electric vehicle poses significant safety risk to the driver and others on the road. DEALER AND MANUFACTURER CONFIRMATION: The failure was confirmed and inspected by the selling Hyundai dealership. Hyundai Motor America (the manufacturer) reviewed the case and issued a formal written determination in February 2026 concluding the defect was unrepairable, accepting a Lemon Law repurchase under Washington State RCW 19.118. This constitutes manufacturer confirmation that the ICCU failure is a non-repairable defect. WARNING SYMPTOMS: Multiple warning lamps and fault messages appeared on the vehicle’s instrument cluster and infotainment display prior to the vehicle becoming fully undriveable. These warnings preceded the total loss of propulsion. ADDITIONAL NOTE: Despite issuing a written Lemon Law repurchase acceptance in February 2026, Hyundai Motor America has failed to execute the repurchase for over 23 days past document submission, missing their own stated resolution deadline. This complaint is filed to create a federal record of both the ICCU safety defect and HMA’s failure to honor an accepted Lemon Law repurchase in a timely manner.

The ICCU failed. The car makes a loud pop sound and then the dashboard lights up. You are stranded wherever it fails because the car isn’t drivable after it happens. The car was inspected by the dealership. There were no warnings before it happened.

While charging the vehicle, we heard a loud pop. After starting the vehicle there was a warning to check the electric vehicle system. The car max speed was limited to about 20mph while driving home (it was night and the dealership was closed). The following morning while driving the car to the dealership, a new warning came on to stop the vehicle. A few minutes later, a new light came on showing a turtle icon and the car would only go about 3-4 mph. I barely made it through the busy intersection and was able to pull over before the car completely died. At that point, nothing worked: no electronic locks, no hazard lights, or other safety measures. The car was towed to the dealership (1/2 mile away) where it was diagnosed with an ICCU and fuse failure. Due to a part being backordered, the car sat at the dealership for 86 days before being fixed and returned.

I started driving and pulled out of a parking lot onto a busy road. The ICCU had failed unknownst to me and as I was underway the car started losing power and the dashboard lit up with warnings about the electrical system. I was limited to 25 MPH for a brief time and struggled to turn off into a parking lot amongst much faster traffic. While doing this the car slowed further to 10 MPH. I limped at this speed into the parking lot at which point it turned off and lot all power. This happened over the course of about 30 seconds. If it had happened on a busier road I would have been in trouble. On the highway and it would have been extremely dangerous. It was dangerous enough as is with cars passing me 20+ MPH faster than my car could go. This all occurred with no warning, and is due to an issue with the ICCU in the car that Hyundai has known about for years and has refused to address or fix.

Car suddenly went into limp mode while driving and completely vehicle shutdown soon after. It has been diagnosed at dealership that it is ICCU issue. It would be very dangerous if this happens on highway.

ICCU fuse blew during operation, car went into limp mode. Vehicle is currently being serviced under warranty through Hyundai

The Integrating Charging Control Unit (ICCU) failed while attempting to accelerate onto an Interstate Highway. The car then went into 'Limp' mode which only allowed a sped of 20 mph. Luckily I was able to get to the next exit without getting hit by car already on the highway going ~60-70 mph. The car showed both a 'battery warning' and a 'car over heating' symbol (the car has no engine, so assume it was the battery that over heated). The ICCU was recalled by Hyundai in the 2022-2024 Ioniq5 models, but was not recalled in the 2025 model (which I own). My suggestion is that the 2025 Hyundai Ioniq5 should be added to the the same recall as the 2022-2024 models since it is exhibiting the same problem.

1 Vehicle fails to start x 6 , dealer unable to fix, falsely identified 2 documented DTCs P31C507 specifically indicates a "possible condition with your Vehicle Control Unit (VCU) / Low DC-DC Converter (LDC)" dealer stated as charger problem when this is often associated with thousands of ICCU problems in this vehicle 2 many ADAS cruise control faults. A vehicle slows and, once stopped, at freeway speed on corners or when a large vehicle is in a nearby, separate lane. Fails to detect the vehicle in the next lane when activating lane change. 3. Keys and door locks fail electronic unlock and falsely lock the vehicle on approach. 4 decreased charging speed associated with a known prevalent main battery failure, and occasional main battery cell differential. 5 voice commands fail in the native and CarPlay app 6. Dealers unable to fix, give a delayed 2-week appointment and state that the car is out of service for a week or more with a loaner vehicle.

The ICCU (and the associated fuse blew) while I was driving and it caused the car to be slowed immediately to approximately 20 MPH. This apparently is a huge issue with this vehicle.