Coolant leak acting like blown head gasket. Coolant was leaking into the exhaust system. Defective EHRS system
2021 Hyundai Sonata Hybrid
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2021 Hyundai Sonata Hybrid do not stand out strongly from the model-year median of 23.
About this comparison →How this year compares
Owner complaints by model year
Compare all Sonata Hybrid years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
Limited mileage data: 2 of 53 reports include usable mileage. There isn’t enough coverage to show a useful chart.
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Electrical System. Review the 25 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine. Review the 21 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine And Engine Cooling. Review the 3 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
53 reportsThe car randomly loses power and stalls on the expressway and it states that something is wrong with the hybrid system
The vehicle, after parking, is nonresponsive to the key fob, nor will it start. This can happen at anytime and anywhere. Dealer said "It is possible the integrated 12v battery into the hybrid battery may be faulty. No codes or tests can confirm the issue. The dealer said the key fobs tested ok." My wife works late at night in …
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The vehicle, after parking, is nonresponsive to the key fob, nor will it start. This can happen at anytime and anywhere. Dealer said "It is possible the integrated 12v battery into the hybrid battery may be faulty. No codes or tests can confirm the issue. The dealer said the key fobs tested ok." My wife works late at night in a dark area, this has happened 2 times at her place of work and we are concerned for her safety as she has to wait outside for a tow truck to tow it to the dealer. The first 3 times it occured, this issue started around march of 2024, and repeated every 30-45 days. Now it has happened 2 more times in the last week. No warning lamps or indications of problems. The windshield has distortion within the glass and is not a clear view. It is as though you are looking through the heat of a jet engine trying to focus on what is on the other side. This is a major distraction while driving, reading the heads up display in the car, reading street signs and general navigation of pedestrian and other vehicle traffic. There is no aftermarket film or materials on the windshield. The door handle on the drivers side has a cover plate over the hole where a manual key could be inserted. As a construction worker I have very strong hands and I have a difficult time removing the cover plate. The last time I removed the plate I cut my hand on the interior part of the handle as the cover plate popped off. That is how hard the plate is to remove. My wife cannot remove the cover plate on her own. This system is in place for the manual use of the hidden key inside the key fob to be able to open the door in the event of a power failure of the vehicle. which has now happened randomly 5 times.
My battery has died twice, so dead that I can’t even unlock to car with the remote. The first time I had it jumped and took it to the dealership where they were unable to find anything wrong with it and they told me if it happened again to have it towed in so they could diagnose it while the battery was dead. So that happened ag…
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My battery has died twice, so dead that I can’t even unlock to car with the remote. The first time I had it jumped and took it to the dealership where they were unable to find anything wrong with it and they told me if it happened again to have it towed in so they could diagnose it while the battery was dead. So that happened again and I had it towed in to the dealership in early April. It’s now July and they still have my car and don’t have a diagnosis yet. They have had their field engineers out to run all sorts of tests, but nothing yet. Today they told me they have 3 Sonata hybrids there with the same issue as mine.
Randomly the car will get a message when driving starting “ Check Hybrid system. Turn engine Off” and the car isn’t able to accelerate when this happens. When you cut the engine off the car is unable to start again until it is jumped. I’ve confirmed the battery isn’t the issue however something with the vehicle is wrong. There a…
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Randomly the car will get a message when driving starting “ Check Hybrid system. Turn engine Off” and the car isn’t able to accelerate when this happens. When you cut the engine off the car is unable to start again until it is jumped. I’ve confirmed the battery isn’t the issue however something with the vehicle is wrong. There are many accounts of people online dealing with the same issue.
215/55R17 94V BSW. . Contacted Michelin about two (2) of the four (4) tires DO Not have the date of manufacture on side wall. These tires are direction specific. They should known that. Maybe the date of manufacture is on the inside wall but they should known the the tire is DIRECTIONAL and be on Both sides. I am not going …
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215/55R17 94V BSW. . Contacted Michelin about two (2) of the four (4) tires DO Not have the date of manufacture on side wall. These tires are direction specific. They should known that. Maybe the date of manufacture is on the inside wall but they should known the the tire is DIRECTIONAL and be on Both sides. I am not going to jack up my vehicle and remove the tire to check the code (IF it is only on one sidewall). Will Return tires to Costco where purchased. Michelin has not responded to my emails...
Driving 70 mph, warning lights and alarms "Hybrid System Failure" "Vehicle shutting down" and then it does. No lights, no hazards, no power. Push button battery restart starts it again with no visible issues. Driving 30 mph, warning lights and alarms "Hybrid System Failure" "Vehicle shutting down" and then it does. No lights, n…
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Driving 70 mph, warning lights and alarms "Hybrid System Failure" "Vehicle shutting down" and then it does. No lights, no hazards, no power. Push button battery restart starts it again with no visible issues. Driving 30 mph, warning lights and alarms "Hybrid System Failure" "Vehicle shutting down" and then it does. No lights, no hazards, no power. Push button battery restart starts it again with no visible issues. Driving 58 mph warning lights and alarms "Hybrid System Failure" "Vehicle shutting down" and then it does. No lights, no hazards, no power. Push button battery restart starts it again with no visible issues. ^This is an ongoing issue. It's also been powerless several times while parked.
Driving on the freeway when we got a notice on the dash that we needed to pull over and the vehicle shut down due to a fuse,/battery issue.
My car will power off randomly, or will seem as though there is no power. I have to revert back to the manual key to enter the vehicle and hit the 12vlt reset to power it back on. This happened at least 3 times. Once while operating the vehicle, and twice while the vehicle was left parked. This is not a low battery issue as, the…
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My car will power off randomly, or will seem as though there is no power. I have to revert back to the manual key to enter the vehicle and hit the 12vlt reset to power it back on. This happened at least 3 times. Once while operating the vehicle, and twice while the vehicle was left parked. This is not a low battery issue as, the car will only do this occasionally, and not every time I enter and turn on the vehicle. There is no error code to follow this mishap as all power goes out and the dealer maintenance has nothing to work with.
Integrated 12v battery in hybrid system keep draining out. I have to manually open the car and reset it every time in order to be able to drive.
Official recalls
0No recalls in this snapshot.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
1DP22005 · Pedestrian Alert Sounds
Opened Jan 27, 2023 · Closed Aug 7, 2023
Status: closed (inferred from source dates) · Electrical System:propulsion System
NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, NHTSA opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified NHTSA he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by NHTSA regarding the subject matter of the petition.
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