Which parts fail
Components named in complaints (automatic and manual transmissions, CVT, axles, driveshaft, 4WD/AWD).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Hyundai Sonata Hybrid owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2012 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed and attempting to accelerate up a hill, the vehicle inadvertently lost motive power. Several attempts to restart and jumpstart the vehicle failed. The hybrid system warning light was illuminated on the instrument panel. The vehicle was towed to the residence and later towed to an independent mechanic, who determined that the engine had failed due to metal shavings in the engine oil. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 20V746000 (Engine) however, the VIN was not included. The manufacturer was not notified of the failure. The failure mileage was 55,000.
The contact owns a 2012 Hyundai Sonata Hybrid. The contact stated while driving at various speeds, the vehicle hesitated and stalled while depressing the accelerator pedal. There was no warning light illuminated. The contact had taken the vehicle to multiple independent mechanics who were all unable to diagnose the failure due to no warning lights illuminating on the instrument panel. The contact then had the vehicle towed to the dealer where the mechanic was also unable to diagnose the failure. The mechanic informed her that the transmission needed to be replaced. The vehicle was not repaired. The failure mileage was approximately 130,000.
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.
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.
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. …
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.
First incident, Sunday, September 9, 2018. While driving, car suddenly flashed warning lights, with message pertaining to the battery. Car decelerated extremely rapidly and became harder to steer. Pulled car over out of street as it lost power. It stopped. Lights remained on. Turned car off and then turned it back on. It cranked up and could be driven as if the incident never happened. There were no warning lights or warning message when the car was restarted. Second incident, Monday, September 10, 2018. While driving the car to the dealership for diagnosis of the problem, the car suddenly lost power again, the warning lights flashed again, and again it became hard to steer. This time driver was not able to pull the car over; it stopped in the street. Driver turned the car off, then turned it back on and drove to the nearest service station. …
The car was at a stop light and burst into flames, all of the sonatas have this problem, all sonatas will at the least burn up the engines, transmissions, or batteries due to this problem. Out of 35 sonatas tested 35 had this problem. Contacted Hyundai USA, Hyundai fullerton, Hyundai consumer complaint line and they refuse to do anything about it . Every Sonata hybird in the world, (to the best of my knowledge) will burn up the engine, transmission, or lithium batteries (which will catch fire) between 70,000 &120,000 miles, Hyundai will not warranty the failure, this is caused by a manufacture defect.. …
The car began lurching forward intermittently at highway speeds (65+ MPH) when travelling in a straight line on a flat highway on day 1, after 30 minutes of driving. On day 2, the car failed to shift gears at low speeds (<40 MPH) while decelerating downhill on a city street, after running normally for 30 minutes at highway speeds. It coasted slightly uphill in first gear to the destination on a city street, unable to accelerate from 5mph. It was towed ($88) to a mechanic where it failed a road test, and the transmission and clutch assembly were pronounced dead. A new transmission and clutch assembly were installed and the engine (odo 131,000+) failed to turn over. $650 in labor to diagnose and attempt repair/replacement. Repairs were estimated at $8,100 and the kbb value was less than $3,200. …
Tl* the contact owns a 2012 Hyundai Sonata Hybrid. The contact stated that while driving, an unknown warning light illuminated indicating to stop the vehicle do not drive. The vehicle was taken to clay cooley Hyundai of mesquite (16230 lyndon b johnson fwy, mesquite, tx 75150) and was diagnosed that the fuel pump that go to the transmission failed and was replaced. The contact stated that the vehicle was picked up at the dealer and while leaving the dealer, the vehicle stalled. No warning light was illuminated. Additionally, while depressing the accelerator pedal, the vehicle hesitated and stalled. The vehicle was taken back to the same dealer and the contact was informed that the transmission needed to be replaced. The vehicle was not yet repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 117,000.
Transmission complaints in other Sonata Hybrid years
Frequently asked questions
How common are transmission problems on the 2012 Hyundai Sonata Hybrid?
NHTSA has 30 complaints about the transmission & drivetrain of the 2012 Hyundai Sonata Hybrid, 19% of the model year's 154 complaints. The component named most often is automatic transmission (1 mentions).
Is there a recall for 2012 Hyundai Sonata Hybrid transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2012 Hyundai Sonata Hybrid, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Hyundai Sonata Hybrid transmission problems start?
Half of the complaints with a recorded mileage happened before about 80,000 miles, and 26% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to transmission & drivetrain problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.