2023 Hyundai Ioniq 5 Transmission Problems

Owner reports

Selected complaints filed with NHTSA by 2023 Hyundai Ioniq 5 owners, lightly cleaned up (personal details are redacted by NHTSA).

7 incidents of electrical drive problem incidents 1-3car would not start despite full battery Incident 4 same thing and car went to dealer, they said know problem and they would fix it overnight by downloading new software and charge about $400 for new 12V battery Incident 5 While on freeway using cruise control card speed varied wildly I disabled cruise control and with manual throttle same problem Incident. 6 In middle of traffic car went blank no lights or anything. I tried to restart 3 times and nothing, so I sat back and was in process of calling for tow. I did nothing and car violently accelerated and turned into steel pole. Only injury I had was bump on head that went away. …

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. The collision warning system did not alert, and auto-braking did not occur. The car was in Regen Level 3, and Auto Hold was not activated. In the months prior to this, the car twice had a similar situation when coming to a stop at an intersection with foot on the brake, then suddenly lurched forward, nearly rear-ending a car in front. There was no visible damage to the concrete wall, and a police report was not made. Hyundai says they want to inspect vehicle, but have not done so after a month. It is easy to believe that this was driver error, but it absolutely was not. Car lunged forward and accelerated into a wall with only the brake being applied. …

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. Car taken to dealership for repairs. Dealership trouble shooting identifed failed ICCU with burnt connecter pins. HyundaiCase Management number 42152269 THIS IS A FIRE HAZARD FOR THE CAR AND HOUSE.

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. When using the L1-L3 braking energy recovery modes, the deceleration experienced by the car is more or less mild enough that it would be similar to a downshift in a manual transmission car. But the brake lights only illuminate if your foot is fully off the accelerator pedal. I am not aware of the regulations or SAE guidance to know if this is consistent with best practice, but it could be better with the brake light coming on once a certain deceleration (x m/s2) is reached. It is my opinion that a software change in the car's ECU could effect a fix for this. …

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. Second time was in normal mode Friday 5/12, 55% battery 72 F outside 1 hr drive 50+ miles. Third time was in normal mode and it happened after 42 miles. I scheduled a service after the first incident but they were only able to take it on 5/31. When this happens you lose ability to accelerate and have to coast to the side of road and let it sit for 10+ minutes to clear and then can resume, I would take surface roads after it occurred. Impacts safety for self and others, as it drastically slows without brake lights causing a high chance of being rear ended. The last incident was close to it. …

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. …

On 11/7/25 , we were driving my 2023 Hyundai Ioniq 5 to a friend's home in rural [redacted] , a trip of approximately 160 miles. At around 5:00 PM, we stopped about halfway to our destination to charge the battery. The car would not charge above 47%. While we continued to attempt to charge the battery, the console displayed a Check Electrical System Warning message, and we received the DTC P1AA700 via BlueLink. We were concerned about our safety on the drive up to the mountains. We were afraid the car would stop running on the highway and cause an accident. We were also concerned the car would die in a remote area and we would be stranded. However, the dealership was closed for the weekend. We drove carefully to our friend's home. I contacted Stevens Creek Hyundai on 11/10/25 and arranged to bring the car in on 11/11/25. It had 13,652 miles on it at that time. …

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. Vehicle slowly lost speed as if it was shifted into neutral, forcing us to pull over to the side of the road. Turning vehicle off, waiting for a minute, and turning it back on restored functions. Vehicle malfunction occurred right after a busy intersection on LA highways and we were able to make it to the shoulder, but if it had happened just 1-2 minutes earlier, we would have been in a lot of traffic merging in and out of lanes at significant speeds. There were no warning lights, messages, or auditory alerts during the occurrence. Vehicle simply lost all power. …

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. After taking it to the shop Hyundai Corporate said we need to drive the car again to see if they had fixed it. Approximately 65 miles into the trip it happened again and this time I was almost rear ended and cars were swerving around me on the shoulder to avoid crashing into me. Hyundai is saying that they cannot reproduce the issue but they are not driving the car on the highway for more than 60 miles. The safety of not only myself and my family is at risk as well as other people on the highway behind and next to us. …

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. When the ICCU fails, the vehicle shuts down instantly and becomes completely inoperable. During the most recent incident, I spent more than eight hours on the phone with Hyundai attempting to arrange a tow. When the tow truck finally arrived, the driver instructed me to shift the car into neutral. The moment I did, the car died again and became stuck in neutral, preventing the driver from towing it. He then left, unable to assist, leaving my disabled vehicle parked on a public road - on a hill - where it posed a further safety hazard. …

Related recalls

Transmission complaints in other Ioniq 5 years