2019 Toyota Prius

NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, NHTSA opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified NHTSA he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by NHTSA regarding the subject matter of the petition.

Frequency when I start car makes a very loud , painful high pitch noise for anywhere from 5-15 seconds

NHTSA ID

11749970

Incident

Jul 12, 2026

Body of car has rust perforation starting from the inside working out. This is on the roof, so water incursion will effect airbags and electrical system. FIrst noticed rust bubbles a few years ago, but did not think much of it. Now two body shops have said roof panel needs to be replaced. This is big stuff!

NHTSA ID

11709126

Incident

May 1, 2024

See Attachment

NHTSA ID

11695974

Incident

Oct 28, 2025

Since October 2023, my 2019 Toyota Prius has developed severe and unpredictable driving behavior after a regular brake service, which may have triggered or coincided with a software or ECU update. The car, which had been driving smoothly since I bought it in 2021, suddenly began showing false braking, steering interference, and lane instability — as if the car were trying to “correct” problems that didn’t exist. These interventions often happen on highways or during turns, creating serious safety risks for both driver and passengers. I’ve spent months and thousands of dollars replacing parts, performing alignments, and recalibrating sensors, including at Toyota dealerships. The problem persists because it is software-based, not mechanical. I discovered that in mid–2023, the NHTSA announced upcoming rules requiring Automatic Emergency Braking (AEB) with pedestrian detection by 2029. Around that same time, reports from multiple drivers (Toyota, Honda, Hyundai, Ford, Subaru) began to appear describing the exact same issues. It seems manufacturers began silently updating vehicles to meet anticipated compliance standards. However, this introduced overly sensitive and malfunctioning driver-assist systems. The most alarming part is that the driver cannot fully disable these features — the “off” button only reduces their intervention. This means when the system malfunctions, the driver is forced to operate an unsafe vehicle. As a professional rideshare driver, this problem destroyed my ability to work. Passengers reported me for unsafe driving because of the car’s erratic behavior. I eventually lost my vehicle and income. I believe this is a systemic safety defect linked to premature or unregulated implementation of AEB software. Drivers deserve the right to fully disable malfunctioning systems that endanger lives. This is not just a car issue — it’s a public safety crisis that must be urgently investigated.

NHTSA ID

11692652

Incident

Oct 1, 2023

Coolant system failed because coolant was leaking into catalytic converter. Two mechanics in two different states (one a Toyota dealer) claimed this is defect with 2019 Prius and results in repair costing more than $2000.00 because of this design flaw. Warning light did not come on until coolant was gone.

NHTSA ID

11678811

Incident

Jul 3, 2025

The contact owns a 2019 Toyota Prius. The contact stated there was a coolant leak and the coolant level was low. There was no indication of coolant on the ground. The check engine and engine HOT warning lights were illuminated. The contact stated that the failure was related to TSB: 0135-19. The vehicle was taken to the local dealer where it was diagnosed that there was a coolant leak in the front exhaust pipe heat exchanger. The parts to repair the vehicle were on backorder. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 95,000.

NHTSA ID

11667430

Incident

May 27, 2025

Mileage

95,000 mi

Exhaust heat-exchanger coolant pipe (part of the hybrid cooling loop) on my 2019 Toyota Prius is the system that failed. Safety risk: complete loss of coolant can cause sudden engine overheating and possible power reduction or shutdown while the vehicle is moving. I transport two young children daily; an unexpected stall on a highway or during an intersection turn would put all occupants and surrounding traffic at risk. AutoNation Toyota Mall of Georgia (dealer) inspected the car on 22-May-2025, confirmed the leak, and advised the vehicle is unsafe to drive until the pipe is replaced. Repair estimate is $2,249 parts & labor to replace the front exhaust pipe that is on back order, no ETA. Toyota Corporate (Brand Engagement, Case # 250522002498) is aware; they escalated the file to their Parts Department because the replacement pipe is back-ordered with no estimated arrival date. No other agencies or insurers have inspected the vehicle. Two days before the dealer visit, the warning symbol began flashing briefly at breaking then for longer intervals while driving. On the morning of 22-May-2025 the lamp was flashing more often and longer prompting the service appointment. Dealer found the coolant reservoir completely empty. No prior warning messages had appeared.

NHTSA ID

11663559

Incident

May 22, 2025

* I was pulling into a parking space at a slow speed. When I applied the brake the car accelerated causing the car to scrape the car next to the space. The car then stopped. * The acceleration was out of my control and the brakes did not stop it. Fortunately there was no person in front of me. * The Tow truck operator who came to get the car experienced the same issue when pulling into the bay at the dealer. I do not know about the manufacturer during their inspection as they did not provide me with that information. * Toyota had an inspection performed and that report was submitted to Toyota on August 20. We just received notification from Toyota that they found no problem with the car. * No warning lights noted.

NHTSA ID

11620209

Incident

Jul 31, 2024

Some 2005 – 2026 Toyota vehicles that have undergone water intrusion may exhibit a condition in which a musty odor is present. Follow the procedures in this bulletin to remediate the odor and address this condition. The purpose of this Service Bulletin is to provide general guidelines and procedures for odor remediation. This Service Bulletin provides a guide on how to prepare and treat the interior of the vehicle for odor remediation. Refer to the applicable model and model year Repair Manual and the EPA (Environmental Protection Agency) website for the most up-to-date safety and precautionary guidelines.

Some customers may experience echoing on the line calling the vehicle when using Bluetooth Hands Free. This is caused by the phone Hands Free volume being too low.

Some ECUs can set a DTC that is common with other ECUs. This can lead to accidental use of the wrong repair manual when diagnosing these type of DTCs.

The air conditioning dye injection tool kit has been developed to aid in identifying the location of air conditioning refrigerant leaks. The procedures outlined in this Service Bulletin aid in locating, inspecting, and repairing refrigerant leaks.

Some ECUs can set a DTC that is common with other ECUs. This can lead to accidental use of the wrong repair manual when diagnosing these type of DTCs.

This bulletin includes basic procedures for performing a rescue charge at battery on high voltage (HV) Ni-MH and Li-ion batteries. This bulletin should be used in conjunction with the applicable model and model year Repair Manual while performing the battery rescue charge. The GRX-5100 should be used wherever the Repair Manual references the Toyota Hybrid System (THS) charger.