I am filing this complaint to report a recurring, life-threatening safety defect in my 2025 Kia Carnival Hybrid involving the battery and hybrid propulsion system. This defect has occurred twice, and despite dealer repair attempts, it has not been resolved. On both occasions, while the vehicle was in operation, the hybrid system failed without warning. The vehicle displayed a hybrid system failure alert, lost the ability to accelerate normally, and became unable to maintain safe driving speeds. On the most recent occurrence, the sudden and unexpected loss of vehicle power created an immediate risk of collision. The vehicle’s failure while in traffic nearly resulted in a serious crash. I was driving with passengers at the time. The vehicle was taken to an authorized Kia dealership for repair following each incident. The same defect has now recurred after the first repair was completed, demonstrating that the underlying cause has not been identified or corrected. This defect substantially impairs the safety of the vehicle. The sudden loss of hybrid system function and propulsion while driving at road speed creates a direct and serious risk of accident, injury, or death to the vehicle’s occupants and to other drivers on the road. I am a [XXX] resident and am aware that this defect is not isolated to my vehicle. Numerous other 2025 Kia Carnival Hybrid owners have filed similar NHTSA complaints regarding battery failure and sudden loss of acceleration. I urge the NHTSA to open a formal investigation into this defect and to require Kia Motors America to issue a safety recall. I am currently too frightened to operate this vehicle and request urgent attention to this matter. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Despite being only 18 months old with under 26,000 miles, the vehicle suffered a catastrophic failure with no prior dashboard warnings. While driving at highway speeds, loud cracking noises occurred while the engine was running, though we were able to pull off safely. The incident resulted in a burning smell, fumes, and rapid battery drain; subsequent inspection revealed a sheared tensioner spring and a critical VDCU diagnostic code (P1A7795), indicating a "Check Generator Belt" error and a major hybrid power control system failure.

4/6/2026 vehicle stalled in traffic multiple times, entered "Limp Mode", unable to accelerate after stopping or after deceleration. I had to press the gas to the floor to get the vehicle to move. While driving, if I had to brake or lay off the gas at all, the vehicle would not accelerate back to the original speed quickly. This put myself and my four children at risk of being rear-ended. I drove with the hazard lights on to Kia of Wesley Chapel Service center. The Battery Management System Warning displayed at the time of the stalling. The Kia Access App displayed the BMS Warning and code P0AA600 (High Voltage Isolation Fault). Initially, Kia of Wesley Chapel Service Advisor stated No warnings displayed and No historical or active codes found. I provided a screenshot of the Kia Access App showing the active BMS Warning and active P0AA600 code at 2:48PM on 4/8/2026. The Service Advisor maintained that they could not find any active or history codes. At 3:00PM the same day, the Kia Access App suddenly showed "No Issues Found". The code was obviously manually cleared. I filed a complaint with Kia Customer Care the same day (4/8/2026) and requested a Kia Technical Specialist be assigned to the case. On 4/12/2026, the original Kia Service Advisor stated "the history code has finally appeared which was the one presented in the screenshot but we cannot replace parts based off of a code that is no longer active unfortunately". He stated they would "keep driving and testing" to try and duplicate the issue. The Kia Access App shows the last trip was 4/7/2026 (the day after I dropped off the vehicle). Interestingly, the vehicle was not moved from the drive up lane at the Service Center until 10:40AM that day, after being dropped off at approximately 6PM the evening prior. I believe they could not get the car to move the evening of 4/6/2026. The vehicle remains at Kia of Wesley Chapel. I am sending the Motor Vehicle Defect Notification to Kia Corporate today.

The vehicle shows a Driver Assistance System Warning randomly. Then the vehicle is unable to accelerate past ~30MPH. We almost got hit when this happened. The warning does not show up in notifications nor does it show up in diagnostics. It gets reverts back to normal when the vehicle is turned off then turned back on. It seems to reset.

While driving the car it will stick in the electric mode and not go back into gas mode. You will only be able to go up to 30-35 miles an hour and in order to fix this issue as of right now all I could do was have to pull over to the side of the road put the car in park turn it off and turn it back on. I worry that this issue will be even worse if I was on the interstate and my car was getting stuck in electric mode and then it’s a safety issue, especially since I have kids in the car. I’m majority of the time being a minivan. I have seen other people post on forms about this issue and it not being fixed by Kia