VEHICLE SPEED CONTROL,FUEL/PROPULSION SYSTEM07/10/2026
On five separate occasions, while turning onto a high-speed roadway and attempting to accelerate to the flow of traffic, the vehicle suddenly lost the ability to accelerate. Despite pressing the accelerator, the vehicle would not exceed approximately 35 mph and then began to decelerate. During both incidents, a "Check Hybrid System" warning appeared, and I was forced to quickly pull over to the side of the high-speed road. The vehicle would only return to normal operation after it was turned off and restarted. This loss of power while merging into traffic created an extremely dangerous situation. Having three young children in the vehicle made the experience especially frightening, and I no longer have confidence that the vehicle can be relied upon to operate safely. Because this defect affects the vehicle's ability to accelerate safely in traffic, I am deeply concerned that it could result in a serious collision if it happens again. I took it into the dealership and the service center experienced the same issue. They thought they had resolved the issue and that it was a "one off" occurrence but it happened to me again just 3 weeks after the attempted repair. This time the engine light came on after the "Check Hybrid System" warning light.
VEHICLE SPEED CONTROL07/04/2026
I live in [XXX]. On the way to [XXX], out of no where the car stopped accelerating. Was in eco mode at the time and dropped completely while trying to accelerate in the middle of the road. Pulled over completely turned off the car checked the engine nothing seemed out of the ordinary. Ran the diagnostics from the car and didn’t show any errors. Turned off again for a bit and turn on and everything was fine. Moved from eco to smart and turned around worked fine for about 5 m so we thought everything was on and tried to go back north to finish our trip and while on smart mode started to accelerate again and didn’t want to accelerate. Turned around and decided best to take it to dealership Monday. We have about another 1 hour to 2 hours to get home and it’s working fine in smart mode but it shouldn’t randomly drop acceleration at all in the middle of driving. Only at 16,487 miles. Doing it again only driving 33 m an hour and in smart mode. Not even going uphill just dropped acceleration while driving around town. About 15 m after. There’s still no error happening when it happens each time. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
ELECTRICAL SYSTEM,FORWARD COLLISION AVOIDANCE06/26/2026
The vehicle began shaking and having ABS problems when driving at ~30 mph after having driven for several miles without issue. The vehicle did not have any history of problems or recent symptoms and was just over one year old. The vehicle was towed to the dealership. The dealership reported a broken driver side front wheel speed sensor wire and attributed it to rodent damage without other evidence.
ENGINE06/16/2026
Van made a loud pop noise and lost power. The HSG belt tensioner spring fell off it's seat loosing tension on the HSG belt. Was unsafe but luckily it happened before getting on the freeway, and coasted into a parking lot. Yes, it's at the dealership getting a replacement tensioner and belt. I believe so. No notification prior to failure, it was sudden.
ELECTRICAL SYSTEM,ENGINE06/01/2026
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)
STRUCTURE05/01/2026
The contact owns a 2025 Kia Carnival. The contact stated that while driving in warm weather, heat from the exhaust pipe could be felt inside the cabin of the vehicle. As a result, the second row floor would become hot and cause discomfort to occupants seated in the second row. Upon investigation, the contact discovered TSB(Technical Service Bulletin) PI2501, which accurately described the failure the contact had experienced. The vehicle was taken to a dealer where they informed the contact that the TSB remedy was performed on the vehicle prior his ownership. The manufacturer was also notified of the failure and was given the same information as the dealer. The contact was then given a case number and was then referred to the NHTSA Hotline to file a complaint. The vehicle had not been repaired. The failure mileage was approximately 2,5000.
ENGINE05/01/2026
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.
ELECTRICAL SYSTEM,FUEL/PROPULSION SYSTEM04/22/2026
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.
POWER TRAIN,ELECTRICAL SYSTEM,ENGINE02/22/2026
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.
ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM02/18/2026
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
UNKNOWN OR OTHER01/30/2026
When driving my vehicle would not go over 31 MPH. Had to turn the vehicle off then restart to get it to clear.
ELECTRICAL SYSTEM,ENGINE12/15/2025
While driving around, the van will go into "limp mode" effecting my speed and acceleration. Then the battery will become drained and the car alarms me to "Check Hybrid System. Stop safely." It seems the hybrid system fails to switch from battery to engine when the battery gets too low, creating the alert. While the vehicle is still running, I will check the diagnostics on the dashboard and it shows no faults: "all systems normal." This is very dangerous as the vehicle can stop running at any moment and could leave me stranded in the middle of the road. I brought the vehicle into the dealership, but they were unable to recreate the problem. While the vehicle was at the dealership, they performed the HVAC control unit upgrade due to a recall. After receiving the vehicle back, this issue has persisted. I do not know if the dealership inspected the vehicle. No other company or entity has inspected the van. This issue first appeared in the first week of November 2025. The issue didn't happen again until 2 weeks later. Now the issue persists almost daily.
Showing 12 of 52 complaints.
