2025 Kia Carnival Hybrid: stuck in gear or won't shift

Filed Oct 22, 2026 · Acceleration, Fuel system · TX

My 2025 Kia Carnival Hybrid was purchased new in January 2025. The problem began almost immediately, with the vehicle first presented to an authorized Kia dealer for this condition at only 810 miles. The vehicle repeatedly and unpredictably enters reduced-power or “limp mode,” causing a sudden loss of normal acceleration and limiting it to approximately 35 mph. This creates a serious safety risk on highways, while merging, crossing intersections, or whenever acceleration is needed to respond to traffic. Equally concerning, the vehicle does not consistently display a warning or retain a hard diagnostic error code when the loss of power occurs. Sometimes a check-engine light or “Check Hybrid System - Stop Safely” message appears, but at other times the vehicle enters limp mode with no warning. After turning the vehicle off and restarting it, normal operation may return and the error disappears, leaving the dealer unable to retrieve a stored code showing what occurred. The vehicle has been presented to an authorized Kia dealer for this recurring issue at least five times. In August 2026, it remained in limp mode and had to be towed to the dealer. We were initially told no error code had been found. Near the end of the service period, we were told a code had appeared indicating a faulty sensor, which was replaced, but the reduced-power problem later recurred. The vehicle’s automatically generated August performance report also indicated no vehicle issues despite the August incident. A Kia TechLine case was later opened, but the recurring problem was not identified or permanently corrected. The vehicle is available for inspection.

Filed Oct 2, 2026 · Acceleration, Brakes · TX

This complaint is a follow up to complaint #XXX. I took the car in to Dennis Eakin Kia in [XXX] to repair what caused the car to go into Limp Mode after slamming on the brakes. The dealership did a deep scan of the hybrid control and power train control module for historical or iintermittent codes. They could find none because the car apparently does not save them after the ignition is turned off. They are trashed. They also tried 4 times to re-create the event by slamming on the brakes, but were unable to re create it. They returned the car to me without fixing it. This is another deep -imbedded safety hazard of this car that a well-documented safety hazard from many drivers cannot be fixed because the car trashes any evidence of these incidences. This car is a clear danger to drivers, a danger that can only be fixed through a recall to get them off the road until a fix is executed by the manufacturer. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 30, 2026 · Acceleration, Brakes · TX

I had to slam on my brakes and the car went into Limp Mode, not allowing acceleration above 20 MPh. I drove for a while and then pulled into a parking lot and turned off the car and back on again. I was able to achieve normal acceleration after turning the car back on. We felt unsafe having no control over our speed and cars honking and racing around us. I am afraid to drive my family in this car for fear of having to slam on my brakes at a highway intersection or off/on ramp, which could cause a fatal crash. A Kia dealership is performing a diagnostic now and will advise. The vehicle has not been inspected by another agency. No warning lights went on that I can recall.

Filed Sep 22, 2026 · Electrical, Engine · UT

On random occasions, car will display "check hybrid system" and go into limp mode (limiting speed significantly) check engine, oil, and battery lights also illuminate. Had car serviced twice by dealership who cannot replicate the error, nor can they find any engine codes stored. However, this incident keeps occurring. Planning on having the car serviced again and not picking it up until it's figured out, but also wanted to report this incidence as I have seen several posts with other people complaining of the same issue. Concern is for if this happens randomly at freeway speeds and becomes a serious road hazard.

Filed Apr 22, 2026 · Electrical, Fuel system · FL

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.

Filed Dec 15, 2025 · Electrical, Engine · TX

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.