2024 Hyundai Ioniq 5: battery drain or dead battery

Filed Oct 20, 2026 · Electrical · MA

The vehicle experiences catastrophic, recurring 12V auxiliary battery discharge and complete electrical system collapse due to a suspected repeating failure of the Integrated Charging Control Unit (ICCU). The vehicle was previously serviced for identical 12V power-loss failures and recall interventions in June 2025. Despite those prior repair attempts, the defect has recurred aggressively, resulting in four separate 12V battery collapse events in October 2026 (specifically on October 10, October 13, October 17, and a complete breakdown requiring a flatbed tow on October 19). This defect presents an extreme safety hazard: when the ICCU fails to step down high-voltage power to maintain the 12V system, the vehicle experiences sudden and unannounced loss of electrical power while parked or operating, risking a total loss of motive power, steering resistance, and exterior lighting in traffic. Diagnostic testing confirms internal 12V battery failure with normal resting parasitic draw, indicating the charging system root cause remains unaddressed despite prior manufacturer recall campaigns (such as Recall 272). The vehicle is currently at an authorized dealer awaiting diagnosis and repair.

Filed Aug 19, 2026 · Electrical · CA

After car has been parked, when trying to start car , car turns on briefly saying 12 v battery low come to safe stop. Then car dies. Car isn’t in motion since it’s been parked. First time it happened I needed a tow truck and the tow truck needed to jump my battery. Since then battery keeps dying when trying to start this has happened every time I start the car since July 11 2026

Filed Jun 15, 2026 · Electrical, Engine · AZ

On June 13, 2026, my 2024 Hyundai Ioniq 5 experienced a sudden and dangerous propulsion failure while in active motion. The vehicle had approximately 9,447 miles on it and was at 58% battery charge at the time of the incident. The vehicle was leased in January 2025 and has been serviced exclusively at the Hyundai dealership. While driving with two occupants, the vehicle abruptly lost all ability to accelerate. The dashboard displayed a critical warning: “Stop vehicle and check power supply” along with a red battery icon. This failure occurred without warning and immediately placed us in danger of being struck by surrounding traffic, as the vehicle could no longer maintain speed or respond to throttle input. I was able to coast the vehicle off the roadway. Shortly after stopping, the vehicle issued an additional warning stating that auxiliary functions were draining the battery. Within moments, the vehicle shut itself down completely. This left both occupants stranded in extreme heat (over 100°F) with no air conditioning, no ventilation, and no ability to restart or power the vehicle while waiting for rescue. This created a serious risk of heat-related medical distress in addition to the initial roadway hazard. The vehicle’s complete loss of propulsion followed by a full electrical shutdown represents a severe safety defect. At no point should an electric vehicle with more than half a charge and fewer than 10,000 miles lose propulsion during active driving or shut down all systems while occupants are inside. This incident posed a significant risk of collision, injury, or heat-related harm. I am requesting that the federal safety agency investigate this failure mode, as it may indicate a broader defect affecting the propulsion or battery management systems of the Hyundai Ioniq 5. The vehicle is currently at the Hyundai dealership undergoing diagnostics and they confirmed they had difficulty jumping it to move it from where the tow truck had parked it on arrival.

Filed Apr 15, 2026 · Electrical · TX

Known ICCU issue: the 12v battery died for no reason rendering the car undrivable.

Filed Apr 2, 2026 · Electrical · CA

There were no dash warnings. The car slowed to 20MPH and then stopped just as we were about to pull onto a busy freeway. The dash stayed on and then went blank while I waited for the tow truck to take it back to the dealer. The tow truck driver was unable to move the car without jumping the dead battery to get the car to pull up the tow truck ramp. We were told it was an ICCU failure. The car was in the Hyundai dealer for replacement of the ICCU unit for approximately 10 days.

Filed Feb 25, 2026 · Electrical · MN

12v battery died at 13,484 miles

Filed Jan 30, 2026 · Electrical · NH

The ICCU failed while I was merging onto the highway to take my 15 month old daughter to daycare. I received a warning message “Stop vehicle and check power supply” and the car entered “limp mode” slowing down considerably in the middle of traffic. A turtle icon also appeared on the screen to tell me the vehicle could only move slowly. I was able to pull off into a parking lot. The car battery died. It was 10 degrees F outside. Hyundai towed it to the dealer where they confirmed ICCU failure. The recall software update took place in December 2025. The dealer doesn’t expect to have ICCU replacement parts in stock for 1-2 months due to back order and 10 other ioniq5s are there waiting for the same fix. The vehicle is likely available for inspection by the federal safety agency if the dealer service center allows access.

Filed Jan 28, 2026 · Electrical, Fuel system · CT

12 volt battery drained in my driveway on 1/20. Vehicle was completely dead including door and hatch locks. Roadside assistance jumped the 12 volt battery. Vehicle message said, “Insufficient power. Check Electrical system”. Vehicle was towed to local Hyundai dealer, who diagnosed an ICCU failure. The dealer has four other Ioniq 5s with the same problem. Replacement ICCU is on back order with no ETA for delivery. There were no warnings prior to the ICCU failure. If the vehicle were being driven when this failure occurred, the loss of power would have put all occupants at great risk.

Filed Apr 28, 2025 · Electrical · CA

Battery Drained

Filed Dec 27, 2024 · Electrical · NY

12V battery dead. It is only 5 months and the start battery is dead. I needed jump start and the problem reoccurring. I hear this is a common problem for all HI 5 models. So why it is not part of recall? Dealership is asking money for replacement. Repeated reoccurring dead battery issue.