2025 Hyundai Ioniq 5

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.

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.

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.

iccu failure. Car completely disabled.

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.

Car has worn down both rear tires to wires and dealer has said alignment is way out and could be suspension issues. Checked recalls and don’t see any but it’s clear there is a serious issue as these tires should have worn like this

The driver attention warning feature is defective and often requires you to take your eyes off the road and stare at the DAW sensor in order to eliminate the car's constant "attention" warnings. Even while looking straight ahead while driving, the DAW is often erroneous and will disengage safety features (e.g., lane keeping assist, adaptive cruise control, etc.) because the DAW erroneously thinks that the driver is not paying attention. As another example, if you are driving uphill/downhill or on a curved road and are looking at the road ahead of you at a slight angle, the DAW will erroneously report that the driver isn't paying attention. The system will then disable the cruise control and lane keeping assist, creating a hazardous situation. Alternatively, the driver can look DOWN (not looking at the road) at the DAW sensor and stare at it until the car reacts. This takes your eyes off of the road and creates hazardous situations. As someone who wears prescription glasses, the problem is even worse. I cannot set a comfortable seat/steering wheel configuration where the DAW can "see" through my prescription glasses. If I want to drive in my normal position, I either need to take my glasses off or turn off the safety features (e.g. lane keeping assist and adaptive cruise control) in order to drive. Hyundai is well aware of this problem and it exists across much of the Hyundai and Kia platforms. Dealerships say that the car is working as intended. In reality, the defective DAW system creates more risk and contributes to a significantly less safe ride (as I'm constantly taking my eyes off the road to stare at the darn sensor).

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.

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.

While attempting to operate my 2025 Hyundai Ioniq 5, the vehicle abruptly displayed a 'Check Electric Vehicle System' warning accompanied by a critical red master service light on the dashboard. A diagnostic scan via the factory Bluelink app revealed a hard fault code: DTC P1A9096 (ICCU / DC-DC Converter malfunction). This failure occurred under 7,000 miles, following a previous total 12-volt battery system failure a month prior. Driving the vehicle with this specific code puts the driver at immediate risk of 'Turtle Mode' or a sudden, total loss of motive power while in motion. Living in a mountainous region where the primary thoroughfare (Highway 17) lacks shoulders, an unexpected power failure presents an extreme, unreasonable highway safety risk to myself and surrounding traffic. The vehicle had to be flatbed-towed to a dealership for an entirely new ICCU assembly

ICCU failure. Car slowed ona busy street. Inspected by dealership service and confirmed ICCU failure. The pop sound and then check electrical system warnings.

Car has only 3307 miles and incurred a DTC P1A9096. This meant the vehicle only had power from the 12 volt battery, not traction battery. Luckily, the event happened 3 miles from home and we were able to just make it. Next day upon calling for flatbed tow service, the car generated an additional DTC P05616. 12 volt battery was exhausted and nothing functioned on the car. Had to then call for a different tow truck with dollies. The failure of the ICCU (Integrated Charging Control Unit) was a cause for recall on earlier year's models. This is a major safety issue as failure of the ICCU leaves you stranded with an inoperable vehicle where you cannot even lock the doors. Currently, the vehicle is at the dealer (Lithia Hyundai of Anchorage) for repair.

While using Highway Driving Assist/Lane Following Assist on Interstate highways, lane markings frequently disappear on overpasses and in construction areas. When this occurs, lane-centering assistance silently disengages. The only indication is a small dashboard icon changing color. There is no audible warning, steering wheel vibration, or other prominent alert. The vehicle may begin drifting before the driver realizes steering assistance has been lost. Observed repeatedly on Massachusetts highways, including I-495 and I-290. This creates an unexpected and serious safety issue, potentially resulting in an accident. I had this happen during a recent trip, and multiple times the car wandered towards an adjacent lane. It caused me to lose confidence in the system, and to maintain constant vigilance, gripping the wheel tightly at all times. Had I not done so, I’m sure I would have had an incident. Who watches the dashboard all the time? The driver's eyes are supposed to be on the road ahead, especially when approaching an overpass. Had they incorporated an audible or tactile alert, this would have greatly increased the driver’s awareness and potentially avoid a crash. Since the system obviously knows when it has disengaged, it would be a simple matter to implement this. My preference would be steering wheel vibration.

I pulled my car out of the garage and proceeded to drive up the street. I suddenly heard a weird sound and an emergency warning appeared on my dashboard stating to check vehicle electrical system. I immediately stopped the car and returned it to the garage. Upon turning the car on a second time to check the message a second message appeared saying “stop vehicle and check power supply”. I called Hyundai for a tow truck to have the vehicle towed to the dealer. When I turned on the car to back it out of the garage it got halfway out and the entire system shut down making everything inoperable including flashing emergency lights, windows etc. there was very little time between the warning light going on and the car becoming inoperable. The dealer diagnosed a failure of the ICCU system which has been reported for several years. A quick Google search reveals that many Ionic owners have experienced this failure. I was incredibly lucky that this occurred within a block of my house. The previous night I was driving home on the LA freeways. Had this failure occurred at night on the freeway it could have been life threatening as there is very little time to get to safety and the hazard lights and all electronics become useless. The dealer said that they will be replacing the ICCU system with a better one. If that is the case then why wasn’t this car recalled and the ICCU replaced?

Vehicle was parked in closed garage overnight. In the morning I tried to start the car and it was unresponsive. key fobs, digital keys, NFC cards none of them were able to open the car. Used a physical key to open the door, and then tried to turn the car on, nothing worked all screens remained black and car was unresponsive. AAA confirmed that the 12V battery was fully dead. When they jumped the vehicle we heard a pop in the car, which is a known ICCU failure indication. The car still turned on and was drivable. I got it to the dealership safely and they confirmed that the 12V battery was fully dead and car only turns in if jumped. They also confirmed that the ICCU had a failure as well and they are going to need to replace the entire battery pack/ICCU assembly.

The ICCU failed on my 2025 Ioniq 5 within 3 months of ownership and only 811 miles on it. The weather that morning was slightly chilly but not cold. I turned on the car and put it into reverse and after backing up only a couple feet, I heard a pop and the "Check Vehicle Electrical System" message and warning light came on. I had not DC fast charged the car since owning it and had only charged it on level 2 chargers at about 9.6kw to 12kw. The car was not charging the night before the issue occurred and had not been on the charger for several days previously as the battery level was around 70%. There were no issues or symptoms before prior to the failure. The car was towed to the dealership and the ICCU and high voltage were replaced under warranty. This is a major issue with the car and it keeps on happening to eGMP platform cars. The same issue happened with my 2023 Ioniq 5. Hyundai is not providing any information to consumers if they have actually identified the cause of the frequent failures or have manufactured a new part that corrects the manufacturing defect. Please direct Hyundai to issue a statement if they have found a fix or there needs to be a major recall until they identify and correct the underlying problem with the ICCU.

The Moon Roof glass, which is not designed to open, developed a non-impact, or stress fracture. Since it is not supposed to open, the glass is a structural part of the vehicle. It was not cracked when I first took possession of the vehicle, and since I did not open the interior screen all winter, I never noticed the crack. I reported it to the dealer, but it did not take responsibility or offer a replacement.

I was driving on a busy highway at a high but legal speed. For a few seconds the vehicle appeared to reset. I lost control and the screen went blank. It was a miracle I did not hit another vehicle. I contacted the dealer and they stated unless it was happening frequently - there is nothing they could do. I spent hours on the phone with the dealer attempting to schedule an appointment, they stated their EV person was not available. I contacted Hyundai customer service. They ignored me for months. They assigned me a contact person - but she would never return my calls. I called the main support number and started over after several months. This representative collected all my info - title, purchase receipt, etc - but then closed my case after a couple calls. They totally ignored the concern.

The Driver Attention Warning system fails every time I put the car in Cruise Control. I have adjusted my seat and the steering column but no relief. I have removed my hat and sunglasses with no relief. I have my hands at 8 and 4. The DAW IR tracking causes a visual warning in the dashboard and then a horrific cacophony if I try to ignore the warning. Two weeks ago an OTA was downloaded which purported to improve the sensitivity of head movement. It is not improved, if anything it is quicker to warn. In settings I turned off the Lane Following Assist and Driver Warning Assist each time I start the car. This does nothing to impact the failure of the DAW. The lack of Cruise Control on long drives causes fatigue and does not help with safety. The constant harassment of the DAW warning does not lend to safer driver. This whole system is intrusive and not making driving safer.

Our *2025* Hyundai Ioniq 5 experienced a complete failure of the ICCU (Integrated Charging Control Unit). The car displayed numerous warnings including "Check brake system", "Check 12V battery. Stop safely and engage parking brake", and "Check parking distance warning system". The car stopped working completely and would not turn on again. A towing company had to be called as the car was completely inoperable.