2025 Hyundai Ioniq 5 Electrical Problems

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 repaired and returned, including the approved daily rate and how billing or reimbursement will work. 2. A parts availability check and estimated repair date as soon as the dealer confirms the diagnosis. 3. If the vehicle is out of service for an extended period, reimbursement of my lease payments for the time I cannot use it. 4. Confirmation of the warranty coverage that applies to the ICCU on this VIN, including any extended ICCU coverage. I am keeping a record of the days the vehicle is out of service, starting XXX. Please reply in writing so I have everything documented. Thank you for your help, [XXX] [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11765558

Incident

Sep 19, 2026

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.

NHTSA ID

11762941

Incident

Sep 8, 2026

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)

NHTSA ID

11762663

Incident

Sep 4, 2026

While driving this EV with cruise control on, the dashboard suddenly showed a message that “Smart Cruise Control conditions not met”. Attempting to re-engage the cruise control did not work and then the vehicle suddenly lost all propulsion (pressing the accelerator did nothing). The car quickly slowed to about 20 mph before we could maneuver it to the shoulder and turn it off. After a couple minutes, we restarted the car and drove it to the dealer. There were no other messages or warning lights or indicators. The dealer could not find anything wrong and asked us to pick up the car and resume using it. We use both a home charger (Emporia) and roadside (Tesla) chargers.

NHTSA ID

11761730

Incident

Aug 27, 2026

I heard a loud popped sound from the back of my car while driving home. The car lost power and eventually died on the street. The war displacy came on to tell em to check electrical system. I originally bought th car from Capitol Huyndai in San Jose on September 2025 and it has 5992 miles. I towed the car to Dublin Hyundai for repair and confirmed the DTCP1A9096 for ICCU computer failing to charge the 12 v battery. It was a well known recall . I do not have any update on the repair since 8/25/26. I worry about my safety because the car can lose power while driving

NHTSA ID

11761068

Incident

Aug 22, 2026

My car starting throwing a “check electric vehicle system” warning intermittently beginning on July 7, 2026 which went away when I restarted the car. This happened again on July 27, 2026 three to four times while I was driving. The car did not lose power. As I was going to dealer the warning cleared and no code showed up in my diagnostic history. On August 12, 2026, the car once again showed "check electric vehicle system” and would initially clear when I restarted the car. I then began having intermittent power. Floored, the car would only go 27 mph. Then it would speed up again, then slow again. I was not in “turtle mode.” Luckily, I was able to safely get the car to the dealership without having an accident. DTC P1A8D13 did show in my diagnostics. The technician found that the 12v battery input had melted at the ICCU. This is very dangerous and could have led to a vehicle fire. My 2025 is on its 2nd ICCU (now 3rd) and has not had any recalls, so this is very troubling.

NHTSA ID

11758690

Incident

Jul 7, 2026

ICCU failure. Failure happened while merging onto the road from driveway. Upon failure, 12 V battery was drained and car was immobilized. Prior to car mobilization dash read “Check electrical vehicle system” then many different failures appeared on the dash, then the car shut down. This event left us stranded on the road, unable to move to a safer location. Issue was confirmed with dealer and part had to be replaced. Part was original to the car and issue is known by the manufacturer but not being dealt with publicly.

NHTSA ID

11757520

Incident

Aug 10, 2026

In June 2025, I started a lease on a new Hyundai Ioniq 5 SEL. On August 16, 2026, I attempted to start the car, but it immediately beeped and flashed a warning about the 12V battery (I didn't manage to take a picture). It then showed signs of an electrical issue, like flickering interior and exterior lights. It was undrivable. A short time later, there was no power at all. I took out the old 12V battery and measured the voltage with a multimeter, and observed 3.7V. After putting in a new battery, the car operated normally.

NHTSA ID

11757298

Incident

Aug 16, 2026

I started the car and got the warning "check electric vehicle system." The car then lost power. It would only go 27mph with the accelerator pedal pushed all the way to the floor. My safety was at risk because my car was not responding appropriately to driver input. The car is at the dealership as it is undriveable in this condition. This is the second incident with this vehicle within 6 months.

NHTSA ID

11756602

Incident

Aug 12, 2026

My 2025 Hyundai Ioniq 5 experienced a complete and sudden loss of drive power at high speed, generating open fault code DTC P1A9096 (Internal ICCU Failure) [24V-204]. This failure completely matches the component and safety hazard profile under active Federal Safety Recalls 24V-204 and 24V-868 [24V-204].The vehicle was repaired at an authorized retail facility, Hyundai of El Cajon. The facility's un-finalized pre-invoice explicitly verified the ICCU failure code but deliberately omitted the federal safety recall context, routing the mechanical intervention under an internal manufacturer 'TSB 24-EV-004H' to hide the defect from consumer safety databases [24V-204].This represents a deceptive administrative effort to under-report active federal safety recall failures on newer model inventories across the E-GMP platform architecture [24V-204]. I am requesting a formal safety defect enforcement review into the manufacturer's regional reporting data.

NHTSA ID

11756375

Incident

Jul 18, 2026

The vehicle was released to me as repaired by an authorized Hyundai dealer earlier the same day. While driving home, the vehicle entered reduced-power/turtle mode and lost propulsion capability. This is the third failure of the electrical/propulsion system in under three months on a vehicle less than one year old, and it occurred within hours of a warranty repair.

NHTSA ID

11754835

Incident

Aug 4, 2026

While driving at 65–70 mph in rain, the vehicle emitted a repeated audible alarm from beneath the rear seat, then suffered a complete loss of motive power at highway speed. No warning light, message, or indicator appeared on the instrument cluster at any point. The vehicle was taken to an authorized Hyundai dealer the following day.

NHTSA ID

11754834

Incident

Jul 30, 2026

While operating the vehicle, the instrument cluster displayed a “Check electric vehicle system” warning with a red vehicle-with-exclamation icon. The vehicle failed to charge when plugged in; state of charge was 90%. The vehicle was towed via Bluelink to an authorized Hyundai dealer. No prior issues and no damage history.

NHTSA ID

11754831

Incident

May 15, 2026

Check electric system popped up. DTC: P1AD300 Critical hybrid/ev battery system fault involving abnormal cell voltage deviation 9,902 miles

NHTSA ID

11754271

Incident

Jul 25, 2026

EV system not working on car with 8k miles on it. Dealer backed up and cannot offer rental car. This is a safety issue for me . This is a KNOWN issue for Hyundai and they are not recalling and their dealers are not equipped to resolve quickly.

NHTSA ID

11751511

Incident

Jul 19, 2026

Systemic failure of the electrical architecture and Integrated Charging Control Unit (ICCU) resulting in a sudden, catastrophic loss of motive power. Over 14 months of ownership, this vehicle has suffered four distinct, electrical and charging failures. On June 6, 2026, the vehicle experienced a total ICCU failure. All lights in the car went dark and lost all power without warning, creating an immediate and life-threatening hazard to myself . The vehicle had to be towed. Three prior repair attempts for charging and 12V battery failures were made by the dealer/. They replaced the ICCU, the car currently runs.. The replaced ICCU has not been redesigned and as a result the car is unsafe to take out on the highway or on a long drive.

NHTSA ID

11751250

Incident

Jun 6, 2026

Failure of ICCU and high voltage fuse. Known issue in this vehicle. 2022-24 have been recalled. 2025 needs to be recalled. Warning on dash when it occurred, then 12V battery died. Undrivable. Towed in and repaired under warranty by dealer. But apparently it can happen again because Hyundai doesn’t know how to permanently address the problem.

NHTSA ID

11749630

Incident

Jun 7, 2026

During a family road trip, my 2025 Hyundai Ioniq 5 (~9,000 miles, less than one year old) suddenly showed red "Check Electric Vehicle System" and 12V battery warning lights and then completely lost power. The 12V system failed entirely - the vehicle could not be driven or shifted, and the doors and the rear hatch could not be locked or unlocked. It had to be flat-bedded to a Hyundai dealer because it was completely inoperable. The dealer diagnosed a failed ICCU (Integrated Charging Control Unit) and a blown ICCU safety fuse (fault code P1A9096) and is replacing both under warranty; the component is available for inspection. The ICCU converts high-voltage battery power to charge the 12V system; when it fails, the vehicle loses all electrical power and drive capability. The warning lamps appeared immediately before total power loss, with no prior symptoms at the last scheduled service. This is a known, safety-critical failure on this platform: a sudden, complete loss of power can strand occupants and, if it occurs while driving, cause loss of motive power - a serious crash risk. My vehicle was stationary when it failed, but the same failure at speed would be extremely dangerous. I have video evidence of the car completely bricked out.

NHTSA ID

11749425

Incident

Jun 29, 2026

1. Sudden Unintended Acceleration On two (2) separate occasions, after coming to a complete stop at a red light with foot on the brake pedal, the vehicle suddenly lurched forward on its own. 2. Brake Pedal Malfunction On more than ten (10) occasions, when attempting to stop at a light, the brake pedal briefly behaves like the accelerator for approximately 1–2 seconds. Driver has to release the brake and press it again to restore normal braking function. 3. Doors Unlocking/Opening on Their Own On more than one hundred (100) occasions, approximately 10 minutes after parking — with no key fob or phone nearby — a door opens on its own. Confirmed via mobile app notification and visual confirmation from a distance each time. 4. Apple CarPlay Connectivity Issues CarPlay frequently fails to connect. During phone calls specifically, the connection drops in and out intermittently. 5. Sticky Residue on Door Handles A sticky, adhesive-like residue is present on the interior passenger door grab handle and rear door handles. Residue does not clean off and transfers to hands on every use.

NHTSA ID

11748715

Incident

Sep 3, 2025

1. Sudden Unintended Acceleration On two (2) separate occasions, after coming to a complete stop at a red light with foot on the brake pedal, the vehicle suddenly lurched forward on its own. 2. Brake Pedal Malfunction On more than ten (10) occasions, when attempting to stop at a light, the brake pedal briefly behaves like the accelerator for approximately 1–2 seconds. Driver has to release the brake and press it again to restore normal braking function. 3. Doors Unlocking/Opening on Their Own On more than one hundred (100) occasions, approximately 10 minutes after parking — with no key fob or phone nearby — a door opens on its own. Confirmed via mobile app notification and visual confirmation from a distance each time. 4. Apple CarPlay Connectivity Issues CarPlay frequently fails to connect. During phone calls specifically, the connection drops in and out intermittently. 5. Sticky Residue on Door Handles A sticky, adhesive-like residue is present on the interior passenger door grab handle and rear door handles. Residue does not clean off and transfers to hands on every use.

NHTSA ID

11748714

Incident

Sep 3, 2025

Description of Safety Defect:The integrated Forward Attention Warning (FAW) driver-monitoring camera located on the steering column continuously fails to track facial structures or pupils during routine daytime driving. This occurs despite maintaining a proper driving posture, adjusting the steering column layout, and removing any facial obstructions.Safety Consequences:When the system falsely registers a "distracted driver" state due to its faulty sensor calibration, it routinely triggers erratic high-pitched chimes and immediately disables active highway driver assistance systems, including Highway Driving Assist (HDA), Lane Keeping Assist (LKA), and Smart Cruise Control. This abrupt loss of active steering guidance and vehicle speed maintenance creates sudden, hazardous driving situations on open highways. Furthermore, to get the faulty alert chimes to clear, the driver is forced to take their eyes off the roadway to stare directly into the steering column sensor camera, actively causing driver distraction.

NHTSA ID

11748019

Incident

Jul 2, 2026

iccu failure. Car completely disabled.

NHTSA ID

11746882

Incident

Jun 26, 2026

3/31/2025: New Vehicle leased. 11/24/2025: 12V battery failure. Battery replaced by dealership. 4/22/2026: 12v battery failure. Battery replaced by dealership. 6/7/2026: ICCU failure. Car cannot charge 12v battery. Car in “limp” mode - cannot drive faster than 40 mph while on highway. Fortunately was able get car to safe location to be towed. All three instances appear to be due to the same engineering flaw in the vehicle.

NHTSA ID

11745720

Incident

Jun 7, 2026

ICCU failed with a pop sound in the evening. Next morning, on my way to the dealership, car started fine, alerted me about the “check electric vehicle system”, but drove fine for about a mile. Then the car came to a crawl mode, refusing to go over 20mph and stopped completely with out any indication. Luckily, I was in a quiet neighborhood and was able to steer the car to the curb safely.

NHTSA ID

11744325

Incident

Jun 12, 2026

When I started the car at 10pm , a loud pop was heard and warning lights on the dashboard indicated an electrical problem. I turned off the radio and anything extra that could use up power; during the next 45 minutes I took surface streets instead of the freeway to drive 22 miles back home and speed was limited to 40 mph. The next day the same warning lights were on the dashboard and speed was limited to 20mph; car lost power after 1 block. Car was towed to the dealer, where an ICCU failure and blown fuse in the engine was diagnosed by dealership and replaced.

NHTSA ID

11742619

Incident

Jun 3, 2026