96 of the 1,162 complaints filed about the Hyundai Sonata Hybrid are about the transmission — 8% of everything owners reported. The worst model year for it is 2012.
96
Complaints
8%
Share of all complaints
8
Crashes
1
Fires
POWER TRAIN
While driving and everything is going along fine it will suddenly jerk and make a sound as if I've been hit behind. I'm not sure if it's part of the detached shift cables or transmission or something else. Sometimes it will jerk violently while going uphill also.
NHTSA complaint #11752611 — an unverified report by a vehicle owner.
POWER TRAIN
The primary failure is in the Engine/Powertrain system and Knock Sensor Detection System (KSDS), causing 6 identical sudden engine stalls (OBD-II code P1326) from 09/2000 to 06/2026. Additionally, severe excessive oil consumption was documented during 2 of these diagnostic visits, showing deep-seated engine issues. The vehicle and all records are available for inspection at the Hyundai dealer. Safety was severely threatened on 6 occasions. The vehicle abruptly stalled at 60+ mph in active highway traffic, forcing an immediate engine shutdown. This left me with highly impaired steering and braking control in fast-moving traffic, creating an imminent risk of high-speed rear-end collisions and jeopardizing my life and others. The primary stalling defect and P1326 code were confirmed 6 separate times by the authorized Hyundai dealership. The secondary excessive oil consumption issue was also formally confirmed by the dealer during 2 of those visits. Despite multiple dealership-confirmed diagnoses, no permanent repair has been achieved. The vehicle has been inspected during all 6 visits by dealership technicians. For the current (6th) visit, the dealer could not resolve the recurring defect and formally contacted Hyundai Corporate Technical Support for expert analysis, which is currently ongoing. Except for the first visit, the pattern is identical: the car stalls, the dealer clears codes/replaces KSDS, and it stalls again within 3 weeks. Notably, during the 4th visit, they replaced the Intake Manifold. Now, on this 6th visit, they demand I pay to replace that same part again. This proves they cannot diagnose the root engine failure and are only applying useless, temporary fixes. Prior to all 6 stalls, the flashing Check Engine / Hybrid Warning light triggered on the dashboard. This critical KSDS alert was followed within seconds by a total loss of motive power. Also, a history of rapid engine oil depletion and low-oil alerts was documented in 2 of the diagnostics.
NHTSA complaint #11750679 — an unverified report by a vehicle owner.
POWER TRAIN
Driving at 78 mph and "Check hybrid system" came on, engine and all throttle/electrical shut off and did not regain power. Had to sit for 5-10mins and vehicle eventually regained power after resetting battery and had no issues.
NHTSA complaint #11712021 — an unverified report by a vehicle owner.
POWER TRAIN
See attached document for complaint.
NHTSA complaint #11693887 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11652891 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11627724 — an unverified report by a vehicle owner.
POWER TRAIN
While on the highway vehicle started shaking violently, flashing engine light then service hybrid system along with every light on the dash! Car still running poorly, stiff steering very hard to slow down to get to safety! By the time I was able to pull over the engine was knocking and a burning smell was coming from the engine compartment. I popped the hood shut the car off , the exhaust manifold and converter(in one together) was so hot it was glowing! I’m thankful I was able to get to safety without it catching fire because it was on its way there! I called for a tow and sent it to the dealer where Hyundai is replacing the engine.
NHTSA complaint #11615081 — an unverified report by a vehicle owner.
POWER TRAIN
What component or system failed or malfunctioned, and is it available for inspection upon request? Vehicle stopped accelerating and flashing check engine light went on. Vehicle reported "Check Hybrid System." Dealer believes it was loose pins in a HCULDC connector that may have caused loss of communication. How was your safety or the safety of others put at risk? Lost acceleration on a highway and was nearly hit trying to get off of the road. Has the problem been reproduced or confirmed by a dealer or independent service center? Piazza Hyundai of Pottstown, PA reproduced the issue. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Dealer secured loose pins. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No.
NHTSA complaint #11612874 — an unverified report by a vehicle owner.
POWER TRAIN
While driving, car started to lose power. Warning lights started flashing to turn off vehicle to recharge battery. Car lost all power. Car was towed to dealership. Dealer started diagnostic testing, and first thing that was noted is that all oil had drained from car and that crank shaft may now be damaged. Prior to incident, no warning lights came on for service, engine or oil lamp. Dealer and internet searched confirm this has been happening to this model recently.
NHTSA complaint #11612120 — an unverified report by a vehicle owner.
POWER TRAIN
The contact owns a 2012 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power and the low battery warning light illuminated. In addition, the contact heard a rattling sound coming from the engine before the engine seized. The vehicle was towed to the dealer where it was diagnosed with a failed hybrid system and that the hybrid system needed to be replaced. The contact was also informed that the transmission was not the original transmission, and the cooler was damaged. The manufacturer was not made aware of the failure. The failure mileage was approximately 145,000.
NHTSA complaint #11588669 — an unverified report by a vehicle owner.
POWER TRAIN:AUTOMATIC TRANSMISSION
The contact owns a 2012 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed and depressing the brake pedal, the vehicle lunged forward. The vehicle was taken to an independent mechanic and diagnosed with automatic transmission failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 76,000.
NHTSA complaint #11585898 — an unverified report by a vehicle owner.
POWER TRAIN:AUTOMATIC TRANSMISSION
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed, the message "Turn off the Engine Immediately" was displayed. Several unknown warning lights were illuminated. The vehicle was taken to the dealer, who was unable to duplicate the failure. The vehicle was not repaired. Later, the contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to pull to the shoulder of the roadway, where the vehicle failed to restart with several unknown warning lights illuminated. The vehicle was towed back to the dealer, who then diagnosed failures with the ABS and transmission. The vehicle was repaired, but the failure reoccurred. The manufacturer was notified of the failure but provided no assistance. The failure mileage was unknown.
NHTSA complaint #11583377 — an unverified report by a vehicle owner.
POWER TRAIN
The car did not shift from Drive to Park after coming to a stop and pressing the Park button. This caused the car to roll forward slowly and run into our garage door. This is not the first time the car hasn't shifted.
NHTSA complaint #11574858 — an unverified report by a vehicle owner.
POWER TRAIN
While driving the car completely cut off i could not use my brakes my horn or steering wheel
NHTSA complaint #11572766 — an unverified report by a vehicle owner.
POWER TRAIN
My check Hybrid system light comes on and then my car stops allowing me to drive , the gas stops working ! This happened 3 times on the highway very dangerous
NHTSA complaint #11566685 — an unverified report by a vehicle owner.
POWER TRAIN
While driving, engine alerted that it was overheating. Pulled over and coolant was very low, so I refilled it and then while driving to my family's garage to use the lift, saw white exhaust smoke. Took it to an independent mechanic, and in the ~10 mile trip there, over a quart of coolant had been burned off. He was able to reproduce the issue. No issues with the engine operation, it runs well and efficient, no check engine light. Mechanic found that a coolant line runs to the middle of the exhaust system and that this seems to be the issue. Other owners seem to have reported this same issue with this same model and roughly the same year, in which the muffler assembly needs replaced due to coolant leaking into the exhaust. Only prior issue was less warm air out of the vents for the previous week or so, but no other issues or warnings.
NHTSA complaint #11558373 — an unverified report by a vehicle owner.
POWER TRAIN:AUTOMATIC TRANSMISSION
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed, several unknown warning lights were illuminated. The contact stated that while depressing the brake pedal, the brake pedal went to the floorboard. The contact stated that the warning light to turn off the vehicle was illuminated. The contact turned the vehicle off and the vehicle failed to restart. The vehicle was towed to the dealer; however, the dealer refused to service the vehicle. The vehicle was then towed to the residence. The vehicle was towed to another Hyundai dealer where the vehicle was diagnosed with a failed transmission and battery. The contact was informed that the transmission and battery needed to be replaced. The vehicle was repaired. The contact stated while driving away from the dealer, she heard an unusual knocking sound coming from the engine compartment. The vehicle was taken back to the dealer. The service technician accompanied the contact for a test drive and confirmed the knocking coming from the engine compartment. The contact was informed that the new transmission that was installed was defective, and the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 74,680.
NHTSA complaint #11556952 — an unverified report by a vehicle owner.
POWER TRAIN
Engine Shut Off Without Warning problem of the 2017 Hyundai Sonata Hybrid While driving the car on the freeway, it will jerk forward and then shortly after lose power. I pull over (luckily haven't been killed yet) on the side of the freeway. I've taken my car to a Hyundai dealership third times. All Three time I was stranded on a busy california highway. I have looked into this warning over a year and no one seems to know the problem. This should be a recall and all Hyundai dealers should be made aware of what this warning is. We as Hyundai owners need answers and help.
NHTSA complaint #11553536 — an unverified report by a vehicle owner.
POWER TRAIN
My 2021 Sonata Hybrid Limited has been in the shop for over 3 months. At least 4 times while driving on city streets, I'd receive an error stating problem with hybrid system please turn off vehicle. Car would go into limp mode giving me just enough power to pull off to the side of the road (if possible), then completely shutdown. Fix action is to hit jumpstart button to get the power back to the vehicle in order to power it on again. After those issues battery constantly died and I had to use the physical key to open the door and hit the jumpstart button to get power. Dealer (Hyundai Jim Click East, Tucson, AZ) couldn't find an issue initially stating they could not replicate what I was experiencing. But eventually my patience ran thin and they finally identified a voltage error while in the service department. The rep informed me that the issue lies with the 12v battery which is integrated into the hybrid battery (stupid design). Service tech had to order a 12v battery from Korea (after dismantling the hybrid battery and sending the pics to Hyundai for approval). This was [XXX]. Still waiting on the parts, no updates at this time. There was another sonata hybrid limited like mine also at the dealership for the same issue. This vehicle had been there since June. They were able to get a new battery for that vehicle, however after a week the same issues reoccurred. I've noticed on Reddit forums that many 2021-2022 sonata hybrid limited owners have been experiencing the same issue, with the same long wait times from Hyundai HQ regarding a solution. At this point I believe it'd be best to open an investigation as there it's been difficult for the dealership and the owners to get any answers from Hyundai regarding this issue. I'd also suggest a recall for this vehicle as it's clearly a widespread problem and hopefully that will give Hyundai the kick in the ass needed to actually take this seriously. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11549899 — an unverified report by a vehicle owner.
POWER TRAIN
The contact owns a 2012 Hyundai Sonata Hybrid. The contact stated while driving at various speeds, the message "Pull Over. Stop the Vehicle" was displayed, and the vehicle failed to respond upon depressing the accelerator pedal. The contact veered to the side of the road and turned off the vehicle. The contact stated that the vehicle became drivable after waiting 30 minutes to an hour. The contact stated that the failure had been recurring while driving. Additionally, the contact stated that while reversing and depressing the accelerator pedal, the vehicle jerked, made an abnormally loud sound, and failed to respond. The contact shifted into park(P) and shifted back into reverse(R), and the vehicle jerked and responded. The contact stated that while driving at various speeds and depressing the accelerator pedal, the vehicle jerked and hesitated to respond. There was no warning light illuminated. The contact stated that she had taken the vehicle to an independent mechanic, where a diagnostic test was performed. The contact was referred to the dealer for assistance. The dealer and the manufacturer were not notified of the failure. The vehicle was not repaired. The failure mileage was unknown.
NHTSA complaint #11537898 — an unverified report by a vehicle owner.