2023 Hyundai Sonata Hybrid Problems

UNKNOWN- While driving on highway, from 70 mph speed the car suddenly lost acceleration and speed dropped. No response to accelerator. Even with pushing the accelerator high, car will go in high RPM and speed will barely reach 40 mph. I was lucky that there was no other vehicle behind me, especially heavy automobile like semi truck as it would have crashed in me from behind due to sudden propulsion loss. The car started working fine next day. I took it to dealer and they couldn't find any error code but said it could be 12V battery BMS software update and they updated it. They mentioned that this is NOT a safety issue which is mind-blowing and concerning as this is a MAJOR safety hazard. I would request you to investigate this further and if this is a software issue then please direct Hyundai to update this with all vehicles and cover the cost for those who have had to pay for it.

On 11/28/25 at approximately 6:30 pm, I was driving on a Highway 17 going about 60 mph when my car's engine completely shut down. a "Hybrid System Failure" warning flashed and my car was no longer drivable. The car was towed to the dealership. In mid October 2025, my car stopped running with the same "Hybrid System Failure" warning, but it happened in my driveway. The car was towed to the dealership and supposedly repaired.

UNKNOWN- While driving on highway, from 70 mph speed the car suddenly lost acceleration and speed dropped. No response to accelerator. Even with pushing the accelerator high, car will go in high RPM and speed will barely reach 40 mph. I was lucky that there was no other vehicle behind me, especially heavy automobile like semi truck as it would have crashed in me from behind due to sudden propulsion loss. The car started working fine next day. I took it to dealer and they couldn't find any error code but said it could be 12V battery BMS software update and they updated it. They mentioned that this is NOT a safety issue which is mind-blowing and concerning as this is a MAJOR safety hazard. I would request you to investigate this further and if this is a software issue then please direct Hyundai to update this with all vehicles and cover the cost for those who have had to pay for it.

My car randomly engaged emergency brakes while driving 70+ mph on the highway with no cars nearby. It almost came to a complete stop but i was able to accelerate again. it was not acting as a safety features because there was not a car close to my front. I am concerned if it happens again i could get in a crash and rear ended. The dealership does not seem concerned

UNKNOWN- While driving on highway, from 70 mph speed the car suddenly lost acceleration and speed dropped. No response to accelerator. Even with pushing the accelerator high, car will go in high RPM and speed will barely reach 40 mph. I was lucky that there was no other vehicle behind me, especially heavy automobile like semi truck as it would have crashed in me from behind due to sudden propulsion loss. The car started working fine next day. I took it to dealer and they couldn't find any error code but said it could be 12V battery BMS software update and they updated it. They mentioned that this is NOT a safety issue which is mind-blowing and concerning as this is a MAJOR safety hazard. I would request you to investigate this further and if this is a software issue then please direct Hyundai to update this with all vehicles and cover the cost for those who have had to pay for it.

On 11/28/25 at approximately 6:30 pm, I was driving on a Highway 17 going about 60 mph when my car's engine completely shut down. a "Hybrid System Failure" warning flashed and my car was no longer drivable. The car was towed to the dealership. In mid October 2025, my car stopped running with the same "Hybrid System Failure" warning, but it happened in my driveway. The car was towed to the dealership and supposedly repaired.

Similar to other stories I’ve read online, my 2023 sonata broke down on the highway a minute after any error signal popping up, in a dangerous location on the highway with no shoulder. Plaza Hyundai dealership was first/last and only people to perform an oil change or service the car. They told me they wouldn’t take the car due to being full after the incident. A Different Hyundai dealership took the car and found the breakdown was due to a missing oil drain plug and the engine leaked all the oil, while noting they didn’t do the previous oil change and there was no external damages. Plaza Hyundai is refusing to claim responsibility and just trying to milk me for much money as possible/get me to purchase a new engine.

The push button shifters do not shift gears, unless the brake is depressed. On a slight incline, it is natural to shift from forward to reverse without braking leaving the driver in the wrong gear. So I have often started forward expecting to go backwards. I accidently ran over a portable toilet trying to quickly reverse out of a driveway on a slight incline. I hope no one has run over a person this way. I have had other close calls. This system is far more dangerous than lever style shifters. Even a little mistiming between brake and shift can leave the car going the wrong way.

Sunroof burst while driving on freeway at a low speed due to heavy traffic. There were no overpasses or bridges above the vehicle when explosion was heard. No point of impact on sunroof from possible rocks and glass is shattered but in one piece and it appears to have burst outwards as it’s bowing upwards. Sunroof had rarely ever been used prior to this and vehicle is only 1 year old. Only some tiny pieces of glass came off initially, but headliner collected them instead of landing on driver/passenger while driving.

Moonroof shattered yes could have lost control due to fright/heart attack no Insurance said it happens to Hyundai often no warning at all

Water continues to gush out of the driver side passenger door when opened after raining. I also found out on Friday, July 30, 2023, that water has been leaking into the trunk of my brand-new car since purchasing it on May 10, 2023. It's a hybrid. [XXX], Pearson Hyundai's New Car Sales Manager (who I bought my car from), and I are extremely concerned about water leaking into the trunk of an electric vehicle which puts me, my family and anyone else who rides in the car at potential risk. Currently my car is at Pearson Hyundai again to fix this issue for the fourth time. Attached are the three previous service invoices that I've received. If needed, I can provide three videos that I recorded of the same issue on May 30th, June 17th and July 1st. Please know that I have also shared the videos with [XXX], Pearson Hyundai's Service Manager and [XXX], Pearson's Service Advisor. On July 3, 2023, I filed a report with Hyundai Customer Service. The Case Number is [XXX]. The last text I received from [XXX], Pearson's Service Manager, yesterday (7/5/23) follows: "I’m sorry I don’t have any answers yet, we’re trying to figure this out, I’m even reaching out to somebody I know when the collision industry that understands body framing-- Sent from Gmail Mobile" INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

The Hyundai Sonata was brought to a stop in a parking lot. When the driver went to put it in park, the vehicle accelerated across the parking lot and smashed into a solid wall. The driver broke her right ankle from standing on the brake pedal. The brakes were ineffective at stopping the vehicle. The collision avoidance system failed to activate or warn of the impending collision. The driver and passenger were severely injured and the car is considered a total loss. There were numerous other injuries sustained. No one outside of the vehicle was injured.