2021 Hyundai Sonata Hybrid Fuel system Problems

“Battery keeps dying randomly. Approximately once every other week and I drive 12k miles a year… dealership reassures me it’s find. Found numerous reports of other Sonota Hybrid users experiencing a similar issue.”

“The vehicle was brought to an authorized Hyundai dealer to have Service Campaign TBH and 94B completed. These campaigns were explicitly designed to prevent known mechanical defects (cracked EHRS assemblies and high-voltage battery errors). The software patches failed to protect the vehicle. The physical hardware has now catastrophically failed exactly as predicted by the campaign, resulting in extreme engine overheating and a physically swollen high-voltage battery pack. …”

“When I arrived in the parking lot and selected the R (reverse), the vehicle stayed in the D (Drive) although that it was moving backwards and was able to park it. The shift selector was stuck in DRIVE (Drive) leaving the vehicle on but not operational. After several attempts to allow the vehicle to cool and the battery to reset, (30 minutes_ later), the car started and took the vehicle to be serviced. The vehicle technician said they had a difficult time diagnosing the vehicle because it was giving different codes. …”

“Incident sounds similar to those experienced with the dual clutch transmissions. November 2022, all of the vehicle warning lights were on and remained on. The vehicle would not move and the transmission selector/shifter was locked in place. Working with the local service/dealership, the vehicle was repaired after 3 weeks with a new transmission shift actuator (or possibly other part). Similarity in the experience and possibility of risk with little information about trends or others in similar situations or resolution. …”