Integrated Charging Control Unit failure. Common issue apparently and I've been waiting over a month for a repair. No loaner offered. Could not guarantee that it won't happen again as it's a "common issue. "
2025 Hyundai Ioniq 5 electrical complaints
Page 3 of 9: complaints 41 to 70 of 229, newest first, as owners wrote them.
ICCU / 12‑V failure & repair – 2025 Ioniq 5 (Illinois) Bought my 2025 Ioniq 5 new in Feb 2025. On 4/21/26, at about 8,653 miles, I suddenly got a red battery icon and “Stop vehicle and check power supply” while driving. I pulled over, limped it home, and it wouldn’t reliably go into READY. Bluelink showed DTC P1A9096 (Electric Vehicle / “Air Flap”), so I had it flat‑bedded to Happy Hyundai of Libertyville. They confirmed ICCU/12‑V system failure. On 4/29/26 they completed the fix under recall/warranty. Key detail: they installed the latest ICCU revision, part# 36401‑1XAD6. They also replaced the ICCU high‑voltage fuse and the 12‑V battery (Interstate H5).
1. The repair work was done at San Leandro Hyundai service department. I do not have the parts that were worked on. 2. Fortunately, both incidents happened when the car was parked at home. The unpredictable nature of the issue though, raises safety concerns as it's unknown when the car is going to die. 3. I have repair orders from San Leandro Hyundai service department of the error codes and repair work conducted. 4. Unknown. I assume the dealership sent the faulty ICCU back to the manufacturer. 5. For the first incident, yes, there were brief notifications on the dashboard about the battery discharging. That was happening for a couple of months prior to the car dying the first time, Feb 9, 2026. For the second incident, no there were no warning messages before the car died the second time Apr 27, 2026. SUMMARY OF INCIDENTS Incident #1 — February 2026 — ICCU failure, vehicle towed to dealer — DTC P1A9096 fault code identified — 22 days out of service — ICCU assembly and high voltage fuse (H110) replaced — 12V battery tested healthy but not replaced, despite Service Advisor Alexa's explicit assurance that replacement was standard protocol for this repair type — Rental reimbursement of $209.96 still outstanding — Maintenance warning appeared approximately one month post-repair; dismissed by resetting service clock with no diagnosis Incident #2 — Current (April 2026) — 12V battery drained to 0%, vehicle completely unresponsive, towed to dealer — Hyundai app showed 47% battery and 'all systems normal' at point of complete failure — D00 fault code identified on 12V battery; sensors reactivated and battery recharged — Traction battery range reduced approximately 50% (~150 miles vs. expected ~344 miles); attributed to battery learning reset, root cause unknown — 4 panic notifications received from Hyundai app on April 30, 2026 while vehicle is in dealer's possession — cause unknown
The contact leased a 2025 Hyundai Ioniq 5. The contact stated that while driving at 25 mph, the battery warning light, reduced power warning light, and an unknown warning light depicting a vehicle with an exclamation mark illuminated. Additionally, a "stop vehicle and check power supply" message appeared, and the vehicle lost power. The driver steered to the side of the road, and the vehicle was towed to a dealer. It was diagnosed that the ICCU unit and ICCU fuse were defective and needed replacement. The vehicle was repaired, and the manufacturer was notified of the failure. The failure occurred at approximately 82,069 miles.
ICCU failure at 6,126 miles. Vehicle went into limp mode and had to be towed.
While backing out of my driveway at less than 5 mph, I heard a sudden loud pop noise from the rear of the vehicle, immediately followed by a dashboard warning: 'Check Electric Vehicle System.' Since I was still in my driveway, I was able to safely park and exit the vehicle. There were no injuries and no other vehicles or property were involved. The vehicle was undriveable and required towing to the dealership. The dealer diagnosed the failure as a defective Integrated Charging Control Unit (ICCU) and replaced the unit. The vehicle was out of service for approximately 6 days.
While driving on [XXX] , I heard a 'pop' towards the rear of the car. A dashboard warning appeared notifying me of an electrical fault. The car went into 'limp' mode, which allowed me to drive no faster than around 25 mph. Fortunately, I was within a half mile of my home, so I was able to do a U turn and return home. I called a tow truck, which towed the car to the local Hyundai dealer in Lebanon, NH. This was a Saturday in February, 2026, so dealer inspection did not occur until the following Monday. The dealer confirmed that the problem was a failed ICCU assembly and the associated high voltage fuse. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
ICCU blew while driving and immediately slowed me to 45 mph
Vehicle shut down with minimal warning due to “integrated charging control unit” failure. Vehicle left my wife stranded on rural road. Current mileage is 12k.
ICCU failed and blew high power fuse. Car displayed warning and only drove slowly. I went to the selling dealer and they confirmed the ICCU and fuse failure.
I was driving on the highway when the car suddenly flashed a “check power supply” warning and then immediately shut down. I was traveling approximately 55 mph when the car came to a sudden stop and I was almost rear-ended as a consequence. I was not rear ended because I had a wide shoulder to immediately pull over onto, but if this had happened in a location without a shoulder, it likely would have caused an accident.
Vehicle unexpectedly ceased to work. A loud pop sound then a message to check electrical system. Vehicle reverted to “limp mode” leaving me at a max of 15 mph. Terribly unsafe and extremely, concerningly widespread ICCU failure across Hyundai EV models For 5+ years is unacceptable
Car charged as scheduled overnight 3/28/26 but was dead the morning of 3/29/26 and when it was jumped gave error "Battery overheated, please stop and exit vehicle" and "check electrical system" - vehicle has been in shop for 16 days, no diagnosis except that it "probably" needs a HV battery.
I heard a loud pop and my car died and was undriveable in about 5 minutes. Told it was my iccu failure and fuse popping. Apparently this is a common issue. I was almost killed as I was kn thr interstate and needed to be towed. Nothing worked
2025 Hyundai Ioniq 5 XRT, VIN [XXX] . Four 12V battery failures requiring jump-starts in under 800 miles of ownership. No fault codes stored at any failure event. Visit 1 (01/12/26, ~100 mi, RO HYCS79193): Factory OEM battery confirmed failed by GDS. Replaced under warranty. Visit 2 (01/30/26, ~300 mi): Second OEM battery confirmed failed by GDS. Replaced. Visit 3 (03/31/26, ~800 mi): Aftermarket AGM tested healthy but required jump-starts. GDS recorded 12V SOC dropping from 99% to 21% then recovering to 79% — consistent with intermittent LDC output interruption, not parasitic drain. Hyundai Techline contacted. No repair performed. Visit 4 (04/08/26, ~800 mi): AGM measured 5.5V, required jump-start. Maryland Lemon Law notice submitted to Hyundai Motor America. The Ioniq 5 has no alternator — the 12V system depends entirely on the ICCU’s DC-DC converter. Hyundai has acknowledged this ICCU defect under the federal safety agency Recalls 24V‑204 and 24V‑868, covering 2022–2024 Ioniq 5 models. The 2025 model uses the same E-GMP platform and ICCU architecture but is excluded from both recalls. My symptoms — repeated battery failure with no DTCs, confirmed SOC anomaly on GDS, failure across two battery chemistries — match the subclinical LDC failure mode documented in those recalls. A Hyundai North America case is open and engineering has been engaged. No repair has resolved the defect. I request the federal safety agency investigate whether the 2025 Ioniq 5 is affected by this defect and consider expanding Recall 24V‑868 to the 2025 model year. Please add this complaint to Investigation PE23-011. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
The Integrated Charging Control Unit (ICCU) failed after just 7400 miles on 2-6-2026. The vehicle would not drive faster than 25 miles per hour and had to be towed to the dealership for repair, where it took approximately one month to be returned to me. There was a "Check electric vehicle system" message on the dashboard.
The 12V battery in my 2025 Hyundai Ioniq 5 failed under normal use, causing repeated loss of vehicle function. Voltage measured ~12.3V at rest, dropping to ~12.0V when opening the door, and collapsing to ~11V then ~9V under light load (headlights), resulting in system shutdown. After a failed start attempt, the vehicle experienced a brownout followed by a complete loss of 12V power for approximately 5 minutes while the battery was replaced. After installing a known-good replacement battery, the vehicle powered up and the instrument cluster displayed “The vehicle is On, Ready” without pressing the start button or providing any operator input. Due to safety concerns, I did not attempt to move the vehicle. Concern: After a complete loss of control power, the vehicle appears capable of entering or reporting a Ready state without explicit operator action. A vehicle should not present or enter a drive-ready state following a power interruption without a new, deliberate user command. This behavior is unpredictable and could present a safety risk if the system were to enable propulsion or mislead the operator about the vehicle’s state. At minimum, it indicates improper state recovery after a power failure.
On April 1, 2026, my 2025 Hyundai IONIQ 5 experienced a cascading electrical failure. The vehicle first displayed a warning about a problem with the on-board charger, followed shortly by an alarm and the 'Stop Vehicle and Check Power Supply' warning with a red 12V battery indicator, rendering the vehicle unsafe to drive. Had I been on the freeway this would have been extremely dangerous. My Bluelink diagnostics history confirms three fault codes from that date: P1A9096 (ICCU fault, Electric Vehicle / Air Flap system, still Open as of 4/3/2026), and P056216 (Voltage Regulation fault, Hybrid Control system, reported twice), consistent with a cascading ICCU failure causing 12V system collapse.
The vehicle flashed a warning not to drive the car because of an electrical system problem after a loud popping noise. I had the car towed to a dealership who told me the Integrated Charging Controller Unit had failed. The car is only 9 months old with under 5000 miles.
ICCU completely went out. Had to have the ICCU replaced with an upgraded one, fuse replaced and software was updated.
Integrated Charging Control Unit (ICCU) failure leading to a loud popping sound from the rear, total loss of drive power.
Driving and lost power in vehicle it wasn't able to accelerate and resulted in getting stranded. Power would then be restored and then lost randomly. Dealer said it was the ICCU that was faulty.
For the HYUNDAI Ioniq 5 XRT, the ICCU, fuse and perhaps hybrid battery malfunctioned. We were in a disabled car on a 4 lane highway with traffic: On February 10, 2026, as we drove out of our home we heard a loud pop. As we got out onto a large 4 lane road near our house, the notice “Check Electrical System” came on and the car’s power was drastically reduced. We made a U turn and drove (20 mph) back to our driveway. We were fortunate that this was mid-day and the road was relatively clear. Normally this is an extremely busy road with traffic moving at 40-50 mph and we would have had great difficulty even pulling out to the side -- as there is only marginal side space on this road. Hyundai has confirmed to us that the ICCU and a related fuse failed. They also think the hybrid battery is also involved and they are testing to confirm that. We had no warning at all -- except for the electrical warning that came on as the car's power was reduced. The car had charged normally and had had no warning signals/signs at all.
March 19, 2026, the car left my 18 y.o. daughter stranded at 10:00pm in a store parking lot. The car was fine when she went into the store. When she went back to the car, it was completely dead. No power at all. I had to pick her up to bring her home and left the car overnight. Called AAA the next morning. I have already previously reported about this car a few months back when it was in the shop for 3 months. Then, the ICCU and wiring harness were replaced a couple times.
Car showed electrical problem on the dash. Car would not start.
Got "Check Vehicle Electrical system" message. Car stopped running and got turned off. Couldn't jump start too.
I am submitting this complaint regarding a serious safety issue with my vehicle, a Hyundai Ioniq 5, which I purchased new and which currently has only 4,795 miles. The vehicle remains fully covered under the manufacturer’s warranty. Yesterday, March 19th 2026, while driving on a heavily congested street, the vehicle suddenly displayed a warning message stating: “Stop Vehicle and Check Power Supply.” Immediately after, the car began to significantly lose power and slow down in active traffic. This created a dangerous situation, as I was forced to pull over abruptly in a crowded roadway, putting my safety and the safety of others at risk. Due to the severity of the issue, I contacted Hyundai roadside assistance, and the vehicle was towed to Safford Hyundai for inspection and repair. I was informed by the dealership that repairs could take up to four months, and I was not provided with a loaner vehicle or alternative transportation. As a result: I am currently without a vehicle for daily transportation, including commuting to work I have experienced significant stress and anxiety due to the sudden and dangerous nature of the incident I am left without a reasonable remedy despite the vehicle being new and under full warranty This situation raises serious concerns regarding vehicle safety, reliability, and Hyundai’s failure to provide adequate support or transportation during an extended repair period. Given that this is a new vehicle with a critical failure that compromises safety, I am requesting: Immediate assistance with a loaner or rental vehicle at no cost A clear timeline and communication regarding repairs Consideration of further remedies if the vehicle cannot be repaired within a reasonable timeframe, in accordance with applicable consumer protection laws I believe this issue represents a significant defect that substantially impairs the use, value, and safety of the vehicle.
ICCU unit of the car short circuited right in middle of driving and caused the car to go in "limp mode". Sudden pop noise and slowdown created situation where car could be rear-ended. The part has already caused recall for prior model years, but model year for my car is not included in the recall. Based on internet search it is a continued and widely prevalent issue, manufacture has not done enough to fix this and a recall needs to add new model years. Additionally, the parts are backordered and there is no immediate fix.
Iccu failure stopped on road
The Integrated Charging Control Unit (ICCU), part number 36400-1XAD5, failed on my 2025 Hyundai Ioniq 5 SEL RWD at 2138 miles. The ICCU is responsible for charging the 12V auxiliary battery from the high voltage traction battery. DTC P1A9096 was recorded on 03/02/2026. When the ICCU fails, the 12V battery drains because it has no charging source. The vehicle becomes undrivable as all vehicle systems depend on the 12V battery. The vehicle had to be towed on a flatbed truck to Hyundai dealer for diagnosis and repair. The failure was confirmed by the dealer using their diagnostic tools. This is the same ICCU failure mode covered by Hyundai Recalls 257 and 272 for 2022-2024 Ioniq 5 vehicles, however the 2025 Ioniq 5 is not currently included in those recalls despite using the same ICCU architecture. The failure at only 2138 miles on a 2025 model indicates the underlying defect was not resolved with the model year refresh. If this failure had occurred while driving at highway speed rather than while the vehicle was stationary, the progressive loss of motive power could have created a serious safety hazard. the federal safety agency should consider expanding the existing ICCU recall to include 2025 Ioniq 5 vehicles.
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