Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2015 Hyundai Sonata Hybrid owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving 5 MPH and making a left turn, the vehicle made an abnormal knocking sound. The contact stated that upon pulling into an apartment complex parking lot, the contact noticed that there was smoke coming out from underneath the hood. There was no warning light illuminated. The contact immediately parked and exited the vehicle. The contact stated that upon opening the hood, the contact noticed a small fire and was able to extinguish the fire with a water bottle. The contact was able to push the vehicle into a parking space with the assistance of her son. There was no injury sustained. No police report was filed. The vehicle was towed to an independent mechanic, where it was diagnosed that a fluid leak from an unknown hose had caused the fire, and there was a hole in the engine block. …
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated while driving 45 MPH, there was a message that the vehicle was not safe to drive displayed on the instrument panel. The check engine warning light was illuminated. The contact stated that the vehicle began to stall; however, while depressing the accelerator pedal, the vehicle failed to accelerate. The vehicle was not drivable. The contact towed the vehicle to the local dealer, where it was diagnosed with needing both batteries to be replaced. The vehicle was repaired but continued to experience the failure. The contact took the vehicle to a second local dealer: Interstate Hyundai (609 Constitution Dr, West Monroe, LA 71292, [phone]) where it was diagnosed with needing both Manufacturer Communications 964 & 966 to be completed. The dealer completed manufacturer repairs, but the vehicle continued to experience the failure. …
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated while driving 20 mph, the vehicle loss motive power and the check charging system warning light illuminated before the vehicle stalled. The contact was able to coast and move the vehicle to the side of the roadway and waited for several minutes and restarted the vehicle. The contact continued to drive to his destination. The failure recurred several times. The local dealer was contacted and informed of the failure. The contact was informed that since the vehicle was experiencing the failure intermittently, the vehicle could not be diagnosed until the failure occurred and the vehicle was taken in with while the failure was happening. The vehicle was not diagnosed nor repaired. The manufacturer was made aware of the failure. The failure mileage was 29,000.
The contact owns a 2015 Hyundai Sonata Hybrid. The contact took the vehicle to the dealer to be repaired under NHTSA Campaign Number: 23V651000 (Service Brakes, Hydraulic) and Manufacturer recalls: 964 (Auxiliary Canister Installation), 966 (Engine Monitoring Module, ECU Software Update), and 994 (Hybrid Safety Fuse). The contact stated that after the repairs were completed while attempting to start the vehicle at the dealer, the vehicle failed to start. The vehicle remained at the dealer who was unable to determine the cause of the failure. The vehicle had not been repaired. The manufacturer was made aware of the failure and confirmed that the vehicle was not covered under warranty for any further repairs. The failure mileage was 170,000.
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated while driving approximately 60 - 65 MPH, the battery warning light illuminated. The charging system failure message was displayed. The vehicle was taken to the local dealer where it was diagnosed and determined that the system needed to be reprogramed. The vehicle was repaired; however, the failure persisted. While driving at an undisclosed speed, the check engine warning light illuminated, and the vehicle stalled. The vehicle was taken to an unknown local dealer, but the vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 75,000.
The contact owns a 2015 Hyundai Sonata. The contact stated that while driving approximately 65 MPH, the vehicle failed to properly accelerate. Later, while attempting to accelerate from a yield sign, the vehicle suddenly stalled. The vehicle was later towed to the local dealer to be diagnosed, and it was determined that the engine bearings had failed and the engine needed to be replaced. The manufacturer was notified of the failure. The failure mileage was 97,000.
The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that the check engine warning light was illuminated. The vehicle was taken to an independent mechanic who replaced the fuel cap and performed other tests on the engine. The check engine warning light disappeared however, two weeks later the warning light returned. The dealer was contacted and a message was left. The manufacturer was not contacted. The failure mileage was 134,298.
Tl* the contact owns a 2015 Hyundai Sonata Hybrid. While driving 65 MPH, a loud pop sound was heard coming from underneath the vehicle on the front passenger side. The contact noticed smoke coming from the front passenger side floor panel. There were no warning indicators. The contact coasted the vehicle to the side of the road, exited the vehicle, and noticed flames underneath the center of the vehicle. The entire vehicle became engulfed in flames. The fire department was called and extinguished the fire. A fire report was filed. The vehicle was towed to a tow lot. The vehicle was not taken to a dealer or an independent mechanic for diagnostic testing. The vehicle was not repaired. The manufacturer was notified of the failure and did not assist. The approximate failure mileage was 35,000. The VIN was not available. Updated 9/26/18
Tl* the contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that the vehicle had premature engine failure due to sludge and metal fragments entering the engine assembly. The vehicle stalled more than twice. The vehicle was towed to north county Hyundai of carlsbad (5285 car country dr, carlsbad, ca 92008, [phone]) for the first repair. The dealer indicated that they replaced the gsi belts, but the failure recurred. The vehicle was towed to the dealer a second time who indicated that the Hybrid battery detached. The dealer re-attached the battery, but this did not prevent the failure. The vehicle stalled again and was unable to be driven. The manufacturer was notified of the failure and did not assist. The VIN was not included in NHTSA campaign number: 15V568000 (engine and engine cooling). The approximate failure mileage was 88,000.
A few months ago the vehicle stalled at a red light. I found complaints of the same make, year and model stalling on other owners on the internet. Went to dealer and after numerous hours in the shop they could not find the problem. Today my 19 year old daughter was on a four lane highway with no pull off lanes, only cement barriers. The vehicle stalled at 60 MPH. She almost died from being hit by a tractor trailer. She was missed by only a few inches. The vehicle did start again and she got off the highway. Made complaint with Hyundai consumer affairs.
NHTSA investigations
Loss of Motive Power
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021.
Engine complaints in other Sonata Hybrid years
Frequently asked questions
How common are engine problems on the 2015 Hyundai Sonata Hybrid?
NHTSA has 21 complaints about the engine & cooling of the 2015 Hyundai Sonata Hybrid, 39% of the model year's 54 complaints. The component named most often is engine › engine control module (ecu/ecm) (1 mentions).
Is there a recall for 2015 Hyundai Sonata Hybrid engine problems?
No. NHTSA lists no engine & cooling recall for the 2015 Hyundai Sonata Hybrid, though it has 4 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 2015 Hyundai Sonata Hybrid engine problems start?
Half of the complaints with a recorded mileage happened before about 75,000 miles, and 28% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 2 fires and 0 injuries to engine & cooling 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.