2023 Toyota Mirai Problems & Complaints

While driving in traffic, my 2023 Toyota Mirai suffered a sudden and total loss of motive power. The vehicle became completely unresponsive while in 'Drive', presenting a severe safety hazard. The dashboard displayed multiple cascading warnings, including 'FCV System Malfunction', 'Pre-Collision System Malfunction', and 'PKSB Malfunction'. The vehicle had to be towed to Dublin Toyota (Repair Order #653103). The dealership retrieved critical diagnostic code P1DC500 (FC AIR PRESSURE TOO HIGH) and verified the vehicle would not go into 'Ready' mode. The dealer opened Toyota TAS Case #TA26079027. However, the dealership performed no mechanical repairs to address the root cause of the sudden power loss. They simply cleared the safety code, test drove it, and explicitly wrote on the final invoice: 'ADVICE CUSTOMER TO DRIVE VEHICLE UNTIL PROBLEM OCCUR'. Furthermore, they refused to document my stated concerns that the vehicle is unsafe to drive. Returning a vehicle to a customer with an unresolved, life-threatening defect that causes total loss of power at speed is incredibly dangerous.

On January 26, 2026, at approximately 6:50 AM, I experienced a serious safety-related malfunction in my 2023 Toyota Mirai while entering traffic on Inglewood Avenue in Lawndale, California. I was pulling out of a parking lot into active traffic at low speed. At the moment I was entering the roadway, the vehicle suddenly lost propulsion/power without warning. Simultaneously, the vehicle’s infotainment/center display went completely black, consistent with a system reboot or electrical interruption. After a brief pause, the display rebooted and turned back on, and immediately afterward the vehicle unexpectedly surged forward. At the time of the power loss, my foot was lightly on the accelerator pedal as I was merging. When the vehicle’s systems reinitialized, the car applied power consistent with the pedal position, resulting in a sudden forward movement. The accelerator was not fully depressed, and this was not a full-throttle event, but the surge occurred without warning while the vehicle was in active traffic. The sequence of events — loss of propulsion, apparent electronic system reset, followed by unintended propulsion upon re-engagement — created a hazardous situation while entering traffic and raises serious concerns about the vehicle’s electronic control and power management systems. The vehicle’s behavior was unpredictable at a critical moment when controlled acceleration was required, which could have resulted in a collision or injury. There were no warning lights or messages prior to the event. I am reporting this incident because it appears to involve a safety defect related to loss of propulsion and unintended surge while in motion. I am scheduling a service inspection and will request a full diagnostic scan, including history and freeze-frame data from all control modules. Vehicle information: Year/Make/Model: 2023 Toyota Mirai Mileage at incident: approximately 47,033 miles Location: Lawndale, California Speed: Low speed while entering traffic

See attached document for complaint.

Summary of Issue: I am the owner of a Toyota Mirai that suffered a sudden loss of power due to contaminated hydrogen fuel. The incident rendered the vehicle undrivable and raised serious safety concerns, as loss of propulsion in a fuel-cell vehicle can occur without warning while in motion. The vehicle was taken to Toyota of [XXX] for diagnosis and repair, where Toyota confirmed the presence of contaminated fuel. Toyota’s Stance: According to Toyota, the contamination issue was addressed by flushing the contaminated hydrogen from the system and refueling the vehicle. Toyota has stated that this process has restored power and that the company does not accept responsibility for any damage caused by the contamination. They have not disclosed any data on the type or level of contamination found, nor have they provided a written service report detailing inspection results or long-term corrective actions. Owner Concern: Independent research and fuel-cell engineering references indicate that contaminants such as sulfur compounds, carbon monoxide, or heavy metals can permanently degrade or “poison” the fuel-cell stack. Flushing alone cannot reverse such chemical or structural damage. As a result, there is a risk of future performance loss or total stack failure. Without transparency from Toyota regarding contaminant analysis or verification of system integrity, I cannot consider this vehicle safe or reliable to drive. Request for Resolution: I am requesting that Toyota: Provide complete written documentation of the contaminant analysis and testing performed on my vehicle. Disclose the long-term plan for ensuring the fuel-cell stack and related components have not been compromised. Offer either a full buyback/repurchase under applicable consumer protection laws or a complete fuel-cell stack replacement verified by engineering inspection. Until Toyota provides a documented, technically valid repair or an official buyback offer, this issue remains unresolved INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The warning that is supposed to appear every time the car is started that the car will auto shut off after one hour of idling never once appeared. As a result, my husband did not know the auto shut off feature existed on his car. He fell asleep in his car on a hot summer day and when the car auto shut off after an hour, he died of heatstroke. The lack of a warning coupled with the car auto shutting off after an hour was reproduced and confirmed by an independent service center. The car has not been inspected by anyone else. There were no warnings, messages, or other problems prior to my husband’s death. He was not informed of the auto shut off feature at the dealership at the time of purchase and the dashboard warning never once appeared to alert him such a feature existed. He thought it was safe to sleep in his running car. The auto shut off feature does not work properly as there was no warning on the dashboard and does not safeguard against people or animals being in the car at the one hour mark. Toyota needs to know this is a deadly feature and make some serious changes.

The vehicle has an advertised driving range by Toyota of 402 miles , depending on that information as true I attempted a trip about that range . During this trip and all other driving times I have never got more then 260 miles of range .