2023 Hyundai Ioniq 5 Transmission Problems

During level 2 AC charging the circuit breaker in the house tripped. Tried again on a level 1 charger that came with the car and again it tripped the home circuit. Again, the car overloaded the house electricla system to a point it tripped the circuit breaker.

High-voltage battery system failure causing complete loss of propulsion. Vehicle entered "turtle mode" (reduced power warning) at 25% charge, then became completely immobile — unable to move even on flat surface. This has occurred multiple times.

INCIDENT DESCRIPTION: On November 24, 2025, while driving at ~60 MPH on NYS Route 17 (highway) with ~15% battery charge, my 2023 Hyundai IONIQ 5 suddenly entered limp mode and lost motive power. The high-voltage battery state of charge dropped instantly from ~10-15% to 0%, triggering error code P1B9600 (HV battery cell imbalance—cells failing to charge/discharge properly).

ICCU Failure — Severe Safety Risk and Repeated Incident The ICCU in my Hyundai has failed twice. Both times, the car suddenly and completely lost power while I was driving — no warning lights, no gradual slowdown, just total loss of control. This created an extremely dangerous situation that put me, my passengers, and everyone around us at risk.

My car’s ICCU (Integrated Charging Control Unit) failed, causing the 12-volt battery to stop charging and die, leading to a loss of power to the vehicle, resulting in the vehicle being completely immobile. I was driving on a busy road when all of a sudden the car started to slow down dangerously which almost caused the cars behind me to crash into me.

Code P1A9096 Iccu and fuse. The car is currently at a dealer in Barre, VT. While driving numerous warning lights appeared lowering my speed to 10 MPH immediately leaving me vulnerable to a collision in moving traffic.

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.

Driver was moving forward into a space in a parking garage between two other vehicles. Driver had pulled most of the way in and was slowly inching forward. As the car came to a stop, it suddenly lurched forward, hitting a concrete wall.

Driving the vehicle on the highway for longer than 60 miles at highway speeds the vehicle goes into “power limited” mode and a turtle pops up on the screen. You are unable to accelerate the car and once this happens you have to leave the car off for at least 5 minutes and then not drive above 65mph again or it will keep happening over and over.

The car does not switch from Reverse to Drive under certain conditions, resulting in uncommanded reverse motion. Gear selection on the Ioniq 5 is controlled by a twisting knob at the end of a stalk on the steering column. Drive is selected by turning upwards, Reverse by turning downwards.

Driving on freeway when adaptive cruise control turns off and had a sudden complete loss of acceleration, we had steering and brakes only. Sudden reduction of car speed in traffic could cause accident. Has only happened once in 20k miles.

After owning and driving the 2023 Ioniq 5 for about 4 months, the car was driven from Massachusetts to Arizona. After driving across the county at 75 MPH about 50 min on cruse control the car began to lurch, the speed would drop about 3 MPH below the cruse control set point, then accelerate to a mile faster than the set point and then settle down to the set point.

EV goes into power limited mode when on interstate when going ~50 miles while driving 70mph or more. Happened each of my 3 times on interstate of about that distance. First time was Sat 4/29 while in eco mode with 70% battery and 82°F outside, 1 hr drive 50+ miles.

Your Integrated Charging Control Unit (ICCU) failed, leaving you stranded and requiring a tow truck. This component controls the charging system in your electric vehicle. Repair will likely involve replacing the ICCU module.

Your car's ICCU (Integrated Charging Control Unit) failed about a year after receiving a software update that was meant to fix the problem. You're concerned that Hyundai hasn't fully resolved the underlying issue, and you worry the replacement part may fail again for the same reason. The repair will likely involve replacing the ICCU component and potentially applying updated software.

Having the same ICCU Failure that all other Ioniq 5 owners have. On February 26th, I was heading to work when I heard a pop and car displayed warning lights saying check EV system and stop safely. Car was limped home and towed to dealer.

After having service done for the past two ICCU recalls months and months ago, I’m driving along today and hear the loud pop that everyone else reports. My car immediately went to a reduced power state where I was able to limp a bit further until I lost all power.

ICCU failed while at highway speeds (65mph). Car went into 'turtle mode' limiting the car to 10mph. No warnings were provided prior to the incident.

While driving my 2023 Ioniq5 I got a warning on the dashboard about losing power and immedately the car slowed itself down to about 15 MPH, once I was able to get to a safe spot to pull over I stopped the car and it would not start again. I had it towed to the dealer and it has been a week and the ICCU is still on backorder. No idea when I will have the car back.

The car had no power on Monday [XXX]. It was taken taken to Tasca Hyundai in Hartsdale NY. The service manager told me it was the ICCU and 12v battery.

Vehicle experienced sudden loss of power while driving at highway speed. While driving on the interstate at highway speed in dark, snowy, high-traffic conditions, the vehicle displayed a warning about an electrical system fault and instructed me to “stop safely.” The vehicle immediately lost some propulsion and ramped down speed.

Upon entering vehicle in the morning of 12/30/25, a notable smell was first present. After turning on the vehicle, the car dashboard showed a "Check electric vehicle system" warning. The car was not able to be put into any gear besides neutral.

Had all previous open recalls for iccu performed. No previous warning in car. Driving unto free way.

My vehicle displayed a Check Electrical System failure warning and experienced a complete loss of electrical power. Since it is an electric car, the car would no longer run. No light including emergencies lights worked.

The ICCU failed which prevented the car from moving. ICCU was replaced by dealer under warranty. Had to be towed from the roadway.

Vehicle warning alarm came on with message to immediately pull over and check power supply. Towed car to dealer where ICCU and fuse were replaced. This after 1-2 recalls were completed.

One month ago, my car experienced an failure and the warnings on the dash reported to check the electrical supply and then to stop driving the car immediately. I had it towed to a dealership who reported the ICCU failed and it'd take 1-2 weeks to get replacement parts and repair.

While reversing slowly, I heard a "pop" noise (sounded like balloon popping) from the rear of the vehicle, and within 15 seconds later, a "Check Electric Vehicle System" warning appeared on the dash alongside the check engine light. About 5 minutes later, I received another warning that said "Stop Vehicle and Check Power Supply" and noticed the car was losing power.

On March 20, 2025, my 2023 Hyundai Ioniq 5 displayed the error "Stop check vehicle power supply" and abruptly shut down during rush-hour traffic, leaving my young son and me stranded on a heavily congested bridge. Immediately, the car’s display went dark, doors wouldn't unlock, and the gear shifter was immobilized. With no emergency functions available, we were completely trapped.

ICCU failure, loud pop sound and then a "Check Electrical System" then after a minute a turtle icon and the car slowed down and stopped on its own in the middle of a freeway. Hyundai towed it and waiting for repairs. This was highly dangerous stopping in the middle of the freeway with no control over the vehicle and fast cars driving by.

Charging system warning light (for 12volt battery) illuminated on left side of instrument cluster. Warning in center of panel said pull over and stop vehicle. Had vehicle towed to dealership and diagnosis was “failed ICCU”.

ICCU ASSY and Fuse had to be replaced as well as the 12 volt battery which failed a few weeks after. The car lost power on a main road 2/3/25 and we were just able to get into a parking lot. The message to check power supply came on and we lost power immediately.

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.

ICCU error, check power source error then all electrical in the vehicle went out. No power steering, no acceleration, anll screens went black, all recalls addressed.

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.

Failure of the Vehicle Power Supply system. ICCU failure. Car was alerting and would not go over 24mph.

My Hyundai IONIQ5 suddenly lost power while I was driving it. I was only able to go 20 MPH for a short period of time before it completely died. I had to have it towed

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.

I heard a pop from the rear of the car and warnings came up on the dash. The vehicle was power limited and needed to be towed to the dealer. It was diagnosed as an ICCU failure and blown fuse.

First time this occured we were driving in the winter and the car randomly shut down and started saying "Electrical Fault" or something of the sort. Turns out it was an ICCU issue. We got this replaced last year.

While driving, the vehicle displayed a “Check Electrical System” warning and experienced loss of propulsion power. The vehicle became inoperable and required towing. The Hyundai dealer diagnosed failure of the Integrated Charging Control Unit (ICCU), a known failure point on this platform.

While stopped at a stop light, "check electrical system" warning flashed on instrument panel without any prior warning or malfunction. I was only able to move the car about 50 feet before all power and controls failed. I was in a middle lane and was barely able to move the car out of traffic.

I purchased my Hyundai Ioniq 5 on [XXX]. Since then, I have experienced repeated and dangerous failures of the air-conditioning system, which Hyundai and the selling dealership have failed to properly diagnose or repair. On [XXX], while driving, I heard a very loud banging noise coming from the front passenger side of the vehicle.

The car lost its ability to accelerate during rush hour on a very busy interstate while I was in the far left lane. It started by jerking really hard off and on, like a very hard brake for a second, and then normal for a few seconds, and then hard braking again. I could accelerate after the "braking".

Vehicle stopped responding to all inputs while cruising on the highway. Vehicle was charged and running fine up until that point, for about 40 minutes of continuous driving. Accelerator pedal, regen paddle shifters, cruise control buttons all would not work and display was unresponsive.

My Ioniq 5 has encountered the renowned "ICCU" failure -- 35k miles in, 2.5-3yrs of ownership. I had a loud 'pop' noise behind my driver seat occur and then my vehicle went into limp mode. The ICCU failure is confirmed by the dealer, but the part is on massive backorder nationwide...

Was driving in Bellevue, WA leaving a parking lot. Heard a "pop" sound, and immediately had a "Check Electrical System" warning come up on the dash. From previous experience in 2024, was aware this requires immediate dealer inspection, so started driving to the dealer 6 miles away.

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.

Our all-electric AWD Hyundai Ioniq 5 has an issue where the rear motor electric oil pump (EOP) overheats and ceases to function when the problem occurs, which disables the rear motor and effectively causes the car to become a front-wheel drive vehicle with a "hesitation" in the acceleration.

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.

Driving on the freeway at approximately 70 MPH, the car lost the ability to accelerate and started to lose speed. I had my foot on the gas but the speed was dropping. There were no warning lights, messages, or other alerts prior to the loss of acceleration.

I drove on the freeway around 70 miles/H last July 14th, 2023 with my wife. But suddenly the speed dropped down after I dropped my car at NORM REEVES Hyundai dealer. They keep 4 days for the test.

Occasionally, the vehicle sometimes doesn't start and allow me to engage to Drive gear from being turned off/Parked. I sometimes have to turn the car off and back on 1-2 times for the car to start like normal and allow me to select drive or reverse.

Had an ICCU failure that prevented the car from being able to drive.

Car gave an error check electrical system and went into limp mode on highway slowing to 25mph.

2023 Hyundai Ioniq 5 ICCU failed with DTC P1A9096 which renders the vehicle in limp mode once the 12V battery drains. This is a major issue which keeps happening even after severals recalls with software updates related to this problem. When this incident happened I had gotten all the recalls and software updates available for the entire care and still it failed prematurely at 35K miles.

After all of recall software updates were applied the ICCU still failed with no warning beforehand and resulted in power and propulsion failure.

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.

Car stopped driving. got a check power systems error and car went into limp mode then stopped altogether

The ICCU failed, leaving the car with a Check Electrical System failure and ultimately cutting power to the vehicle, forcing driver to pull over and stop.

See uploaded photos and document.

When using the most aggressive braking energy recovery mode in the Hyundai Ioniq 5 (I-Pedal), the brake lights do not illuminate despite the aggressive nature of the braking provided by this mode. This mode brings the car to a full and complete stop and is very similar to commanded braking via the brake pedal.