The first time the "aux" battery was not charging completely. 2nd time pretty much same issue, they claimed to have performed a software update, 3rd time warning lights came on "Problem, check electrical system"..something like this. They told me to bring the vehicle to the dealership. After reading the problems stem from the ICCU, I decided to call them to ask if I should tow it in, due to all the warnings. After this we could not even get into the vehicle or drive it. Took us and the tow driver 4 attempts to get it out of the garage, down driveway and it had to be pulled onto the flat bed. They agreed and said that if there were any tow fees, they would pay them. Furthermore they said they would supply a vehicle to use while mine was being repaired. This was on Jan 25th, they still have not returned my vehicle, claiming they are waiting on parts, I've had to call them to check on it, this week NO contact what so ever.

- Plumas Lake, CA, USA

Was driving the car and electrical system failure alert came on. Could not drive over 20 miles an hour on highway and then car just died once I got on side street

- Decatur, GA, USA

While running errands, my Ioniq 5 suddenly made a pop sound, and the dashboard displayed a -??Check Electrical System-?? warning, followed by a loud alert and a message instructing me to -??Stop Vehicle and Check Power Supply.-?? I was able to safely park in a lot and called for a tow. At that point, the car was still operable, but after being unloaded from the flatbed, it would no longer turn on. The issue was diagnosed as a failed ICCU, and I was informed it will take one month to receive the parts and complete the repair. Had this failure occurred on a highway or busy street, it could have been extremely dangerous. I am fortunate that it happened in a safe location.

- Bellevue, WA, USA

On [XXX], I was pulling into my driveway when I heard a loud -??clunk-?? and an error message came up on the dashboard saying -??Check Electric Vehicle System.-?? I checked the 12V battery which was at 11.9 volts, so I first tried charging it with an external battery charger. However, the error message still came up, and when I tried driving on my street it was limited to 25 miles per hour, and eventually I got the error -??Stop vehicle and check power supply-?? and the car slowed to a crawl. There was no warning prior to the failure. I had the latest ICCU software update recall performed at Capitol Hyundai in San Jose, CA on December 30, 2024. The next day, I had the car towed to Capitol Hyundai; a week later they diagnosed the problem as a blown fuse and ICCU failure. There is no estimate on when they will receive a new ICCU part to repair it. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Santa Cruz, CA, USA

While driving the vehicle on a local road at around 40 mph, check electrical system light came on and I heard a pop sound behind me. The vehicle would suddenly go no faster than 30 mph. Upon further driving, for additional quarter mile, it would drive no faster than 12 mph. I was able to very slowly drive it 1.5 mi back home. Once I arrive home, the vehicle was no longer operational. I confirmed that the 12-volt battery was at an extremely low charge and having the vehicle on would not charge the 12 volt battery. I believe the ICCU failed. I am waiting for Hyundai to further diagnose this.

- Milton, MA, USA

June 2023 - 12 volt battery discharged overnight on consecutive nights. Dealer service eventually claimed that the problem was the navigation head unit was faulty and continued to draw current after the vehicle was turned off. The process took over 4 weeks to remedy since the necessary part was unavailable. January 2025 - While driving, a warning to stop the vehicle and check the power system appeared. After a few minutes the vehicle lost power and went into "limp home mode" which limits the vehicle to 25 mph. This problem was attributed to a failed ICCU. However, due to lack of availability the vehicle has been in the service department of the dealer for 3 weeks (Jan 17,2025 to Feb 4, 2025). The dealer estimates that it will be at least Feb 14, 2025 before the car can be repaired. While these two incidents may be unrelated, the result has been the same: the 12 volt battery does not stay charged up rendering the vehicle unusable. For drivers and passengers it is unsafe to operate the vehicle when speed is limited to 25 mph. I understand there is a recall on this part, but Hyundai's lack of support for providing replacement parts in a timely manner is causing owners of these vehicles to continue to drive them until the part actually fails which often happens at an inopportune time.

- San Jose, CA, USA

There is a known issue with the ICCU fuse. Mine blew this morning while driving and vehicle went into limp mode. Max speed is 20 mph and this is not safe on the highway. Vehicle completely died because the 12V can-??t be charged with the blown fuse.

- Chapin, SC, USA

I was pulling into my driveway and I heard a "clunk" and then an error appeared on the dashboard saying "Check electric vehicle system." My 12V battery then died. After recharging the 12V battery with an external charger, the "Check electric vehicle system" message came up again when I started the car, and I could only drive a block or so before another message on the dashboard said "Stop vehicle and check power supply." I had the vehicle towed to a Hyundai dealer where it is waiting for them to diagnose the problem. I had all of the ICCU software update recalls performed on the vehicle before this latest problem occurred.

- Santa Cruz, CA, USA

This car has had several recalls. On 12/9/24 I brought it to dealer re the ICCU update. Apparently what was done was just a software update. On 1/8/25 while driving 50 mph, the car suddenly lost power in traffic. Flat bedded to the dealer, they had to replace the ICCU. Todays Consumer Reports states that the ICCU recall was to replace the ICCU. Clearly the software update or check FAILED, putting me and other motorists at risk that night. I always thought a recall was a repair/replace situation, not an update/check situation. Being told by the service mgr that after all, it's a $3000 part, so if it's OK they don't just replace it. Huh" What? Not replacing it as a recalled problem is a problem. Their software update failed clearly, and now I'm afraid to use the car other than locally. The warning lamps came on only as soon as power was lost and slimply said "check electrical system". No warning BEFORE the event. I think the manufacturer's solution is a non solution, ineffective and dangerous to the motorists. In addition, I got the 4 or 5 recalls already on this car I've had for under 2 years now from my insurance company, not from Hyundai. What's with that" I would be happy to speak with someone about this. I've called the manufacturer and they read to me off of a script.

- Toms River, NJ, USA

Charging port burned during DC fast charging session, resulting in melted charging pin. Unable to insert CCS connecter due to melted pin obstructing insertion. Further damage to electrical systems unknown. No warning signs shown aside from vehicle charging session ending. Lack of safety systems to prevent melting/burning of charging pins leaves potential for general vehicle fire, battery fire, etc. Dealer has had car in possession for over 10 days with no update. Corporate contact has been unresponsive.

- Newton, MA, USA

I have had my 2023 Ioniq 5 for 13-months. I have had two safety recall services performed - I understand those were ICCU software related. On [XXX] my car sounded a sudden alarm and a warning appeared saying to "STOP and Check Power Supply." I was not able to immediately pull over but found the ability to pull over within about 1/4 mile, the vehicle seemed to be losing power. It was frightening as there were many pedestrians and cyclists and I had no idea what was happening. The car was towed through AAA - we had difficulty getting it onto the truck as there was very little power and almost no power steering. The vehicle is now at the Rowe Hyundai dealership in Westbrook, ME. I was told the ICCU would need to be replaced as well as some kind of fuse. I am not sure I will feel safe driving this vehicle even after it is repaired. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Lincoln, MA, USA

Latest recall had been applied, 2 weeks later a dead 12V. New one put in and 4 weeks later a pop and an immediate pull over vehicle charging system needs inspected. ICCU failure.

- Akron, OH, USA

Vehicle's charging port appears to be overheating to the point that thermal throttling is occurring when attempting to charge. This issue first occurred in mid-May of 2024. Vehicle charged as normal before then. Vehicle was serviced by dealership for this issue on 05/29/2024. A software update was applied that did not solve the problem. In an attempt to find updates on this problem, I contacted Hyundai Customer Care by phone on 05/30/2024. Hyundai Customer Care agent read a scripted response that was first released to the public in 20203 and advised to wait for an unknown amount of time for an unknown fix which may or may not come to pass. Hyundai Customer Care had no updates more recent than the 2023 release from which the Customer Care agent read. This appears to be a known issue with no actual fix available to the customer and no ETA on when such a fix might be released.

- Oak Ridge, TN, USA

First indication something was going awry was when attempting to charge the car. Heard normal click indicating charge had started, but no audible announcement that charging had started. Car started throwing "Check electrical system, " then power plummeted and became unresponsive to accelerator, followed by "Stop car. Check electrical system, " then finally something like, "Battery is being discharged by external devices."** Car had to be towed about 60 miles to nearest Hyundai EV service center. Eight days later, I got a call from service saying that the ICCU needs to be replaced. They will update me once ETA of part is known.

- Goldthwaite, TX, USA

The vehicle made a loud popping noise and lost motive power. Dashboard lit up with battery symbol and said to check electric vehicle system. Dealer service is certain it is an ICCU failure. The vehicle had the software update to -??fix-?? the ICCU issue thousands of miles ago.

- Newton, MA, USA

The car loses power, slows down dramatically, and will not respond to the accelerator pedal. This failure has happened twice. The first time I was driving at about 40MPH on a side street when the car started slowing down with no warning and limped along at about 20MPH. I could not get it to move faster so I put my flashers on and made my way to the side of the street, pulled off of the road and shut the car off. When I restarted the car it drove normally. I reported the failure to Hyundai and they had never heard of this happening. They kept the car for 2 days and couldn't replicate the problem. That was about 2 months ago. Yesterday, 3/4/24, I was on the freeway going about 74MPH using the smart cruise control. I had just changed lanes when the car lost power and I got the message, "Smart cruise conditions not met." My speed dropped to the low 40's as other cars were whipping past me. Even though I floored the accelerator I got no response. I started the flashers, made my way to the right lane and got off on an exit ramp. I pulled off to the side of the ramp, parked the car and turned it off. Once again, when I restarted the car it performed normally. This is very dangerous! I could have easily been rear ended by another, faster car on the freeway since I slowed down so quickly without braking lights lighting. I brought it back to the dealer again today and they have kept it to run diagnostics. I don't expect that they will find any problem this time either.

- Irving, TX, USA

The ICCU has failed after the recall repair was completed in September 2023. When the fuse pops the car indicates a check electric vehicle system message in the driver information screen.

- Charlotte, NC, USA

This model has known issue. As I found after it occurred to my brand new IONIQ 5. It has only 320mi. It had 87% battery and all of sudden it stop on road. No power on dashboard. After taking to service station they found -?? "Inspected and found code P1A9096- DC/ DC converter input voltage sensor fail. Referenced campaign 997 for concern. With code present, per TSB, replace ICCU and fuse." This same issue I noticed in 2022 after reading forum. After putting my car in service station still I don-??t have my car. It-??s almost 17 days. If this car had recall I could have saved my time and unnecessary effort. Plus thank god it was local city read( school zone) if I was in highway and same thing happen to me it might be life threatening situations.

- Parker, CO, USA

Car: 4 month old 2023 Ioniq 5, Starting on September 12, 2023 my car would not take any charge AT ALL, effectively make my car useless as I am down to 10 miles of range. For the next several days I tried multiple chargers at different locations trying both 350 kW and 7kW chargers. Other cars were able to charge their cars immediately after I moved from the charger. I have read that the software update I am going to get will reduce my charging capacity rate to fully charge slower. This car is not performing at the stats I chose it for. I will not be able to use this car if it cannot take fast charge for a full charge. I was not made aware of this issue that was well known to Hyundai (they have been dealing with this issue with its earlier Ioniq models) before going forward with this car. Nor would I have decided on this car if this issue was known to me.

- San Francisco, CA, USA

Rear electric motor overheating on highway and motor shuts off only allowing front motor to work but acceleration is near nothing and is extremely dangerous. No codes or warnings pop up was told by friends with other ioniqs that it's a electric motor oil pump that malfunctions but hyundai refuses to solution ND realize that there is a problem with motor malfunction

- Palmdale, CA, USA