2021 Toyota Prius Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2021 Toyota Prius, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Driver assistance222.2%
- Engine222.2%
- Fuel system222.2%
- Brakes111.1%
- Electrical111.1%
- Other / unspecified111.1%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Driver assistance
Reports naming forward-collision avoidance, lane keeping, back-over prevention, cruise control and related electronic driver-assistance systems.
From owner reports, verbatim
The contact owns a 2021 Toyota Prius. The contact stated while driving approximately 35 - 45 MPH, the vehicle independently accelerated. The brake pedal was depressed but failed to stop the vehicle immediately. The contact swerved around the vehicle in front and ended up on the opposite side of the roadway. The contact attempted to avoid oncoming traffic and swerving around all the other vehicles and ended up in a ravine. The contact's husband depressed the START/STOP button from the passenger’s side to turn off the vehicle, enabling the vehicle to come to a stop. The contact restarted the vehicle and continued to drive the vehicle to the dealer at slow speeds. The dealer was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was made aware of the failure by the dealer. The failure mileage was 56,000.
The Lane keeping assist used in radar cruise control mode during some drive cycles will attempt to maintain the vehicle position to the far extreme of the lane and in some cases actively veer out of the lane. My safety ant others can be put at risk when the vehicle behaves outside of its design parameters like this. To solve the issue the vehicle must be pulled over, turned off, then restarted. After the restart it will resume functioning normally, maintaining lane positioning as intended within the limits of the system. The trigger for this is unknown but could be speculated that it is drive cycle dependent and may start during initialization. The problem has not been reproduced by a dealer or service center due to its intermittent nature. There are no warning indicators or lamps on when this occurs.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
The car accelerated without my foot on the accelerator, brake did not respond, and I had to drive through grass and a rock-filled ditch until after about 10 seconds the car returned to my control.
CARBON MONOXIDE SEEPS INTO THE PASSENGER CAR BUT DILLER CANNOT FIND IT AND DID NOT HAVE TOOLS TO DETECT CO LEVEL IN THE CAR. I CAN'T USE THIS CAR BECAUSE WAS POISONED MANY TIMES AND AFTER A SECOND CHECK-UP, THE LEVEL OF CO BECOMES HIGHER SO I CAN'T DRIVE THE CAR WITHOUT POISONING. PLEASE HELP ME. I AM WORRYING TO SELL MY CAR BECAUSE OTHER DRIVER WILL GET INJURY. THIS IS THE NEW CAR ONLY 7000 MILES.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Fuel system
Reports naming fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks.
From owner reports, verbatim
When i am going down it's charging when the charge reaches 6 from 8 the engine starts working and stop changing at that point and the power continues comes from engine only without the hybrid battery and there are no codes
CARBON MONOXIDE SEEPS INTO THE PASSENGER CAR BUT DILLER CANNOT FIND IT AND DID NOT HAVE TOOLS TO DETECT CO LEVEL IN THE CAR. I CAN'T USE THIS CAR BECAUSE WAS POISONED MANY TIMES AND AFTER A SECOND CHECK-UP, THE LEVEL OF CO BECOMES HIGHER SO I CAN'T DRIVE THE CAR WITHOUT POISONING. PLEASE HELP ME. I AM WORRYING TO SELL MY CAR BECAUSE OTHER DRIVER WILL GET INJURY. THIS IS THE NEW CAR ONLY 7000 MILES.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Brakes
Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.
From owner reports, verbatim
The car accelerated without my foot on the accelerator, brake did not respond, and I had to drive through grass and a rock-filled ditch until after about 10 seconds the car returned to my control.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
The car accelerated without my foot on the accelerator, brake did not respond, and I had to drive through grass and a rock-filled ditch until after about 10 seconds the car returned to my control.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Other / unspecified
Reports whose component NHTSA recorded as unknown, or that do not map to one of the categories above.
From owner reports, verbatim
WHILE DRIVING ON THE I 4 WE HAD A BLOWOUT ON THE REAR PASSENGER TIRE. THE CAR HAD LESS THAN 200 MILES ON IT SO IT WAS BRAND NEW. THE DEALERSHIP FOUND OBJECT IN THE TIRE THAT COULD HAVE CAUSE THE PROBLEM THE ONLY CONCLUSION I COULD COME TO IS THAT THIS TIRE WAS DEFECTIVE. THE DEALERSHIP SAID I COULD HAVE RUN OVER A LARGE OBJECT OR A LARGE POTHOLE, WHICH I DOUBT.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .