2012 Toyota Prius V: brake failure

Filed Sep 16, 2026 · Brakes · 187,000 miles · FL

The contact owns a 2012 Toyota Prius V. The contact stated that while driving 65 MPH, brake fluid was leaking from the vehicle. While driving over 45 MPH, the brake pedal became firm, requiring the driver to exert extra force while depressing the brake pedal; the brakes failed to respond as intended. Additionally, a burning and toxic odor was present during the failure. Multiple warning lights illuminated on the instrument cluster, including the ABS system, parking brake, brake malfunction, and electronic stability warning lights. In addition, the automotive brake system, brake pump, and pressure warning messages were displayed. The vehicle was taken to a local dealer, where it was diagnosed with a failed brake booster assembly after inspection. The dealer determined that the brake booster assembly needed to be replaced. The contact associated the failure with Customer Support Program: 20TE07. The contact was referred to the federal safety agency Hotline by a lawyer, and the contact had found a class action lawsuit related to the failure. The failure mileage was approximately 187,000.

Filed Sep 9, 2026 · Brakes · CA

2012 Toyota Prius v with 89,662 miles. Multiple brake warning lights illuminated, and the vehicle stored diagnostic trouble code C1391, “Abnormal Leak in Accumulator.” The brake booster/accumulator pump is also cycling about every 13 seconds, even when the brake pedal is not being applied. The vehicle and components are available for inspection. My safety concern is that this involves a critical braking-system component. When the warning lights are on, regenerative braking is disabled, and braking behavior changes. I am concerned that continued deterioration could reduce braking performance or result in loss of brake assist. The issue has not yet been formally diagnosed by a Toyota dealer. I scanned the vehicle with a diagnostic scan tool, which currently shows C1391. I also contacted my independent repair shop, which recommended that Toyota diagnose the vehicle because this code is associated with the brake booster/booster pump failure previously addressed by Toyota Customer Support Program 20TE07. The vehicle has not yet been inspected by Toyota, police, insurance, or another manufacturer representative. A Toyota corporate case has been opened and escalated. There were no known brake warning lights before this incident. The problem first became apparent when multiple brake warning lights illuminated. Afterward, I noticed the brake booster pump cycling unusually often. Toyota previously identified C1391 as a qualifying code under 20TE07 for certain 2012–2014 Prius v brake booster/booster pump failures. My vehicle is outside the time-based coverage period despite relatively low mileage. I am reporting this because I am concerned this safety-related failure may continue occurring in similarly aged vehicles.

Filed Jun 23, 2025 · Brakes · VA

While driving on the interstate I went to slow down to merge and my brakes failed. The following warning lights came on: Master Warning Light (yellow), Brake System Warning Light, Brake System warning light (red), ABS Warning Light, and the Slip Indicator light. My vehicle was towed to a Toyota Dealership and after running a diagnostic test, they confirmed that it was the "Break booster with accumulator c1391 stored internal leak of accumulator and need immediate attention" which they quoted at $4,295.68 to fix. After researching the issue saw A Customer Support Program 20TE07 was issued taking responsibility for the faulty Brake Booster Pump Assembly however only covered the repair for a two-year period and only if it was one of the identified diagnostic trouble codes listed in the CSP issued by Toyota but expired in Feb 2022. The code pulled from my vehicle 3 days ago was listed in this document, but the coverage only covers until Feb 2022. This is not a normal wear and tear issue, it is a faulty part that Toyota identified as a life and death safety concern but refuses to do anything about because mine didn't show an issue within their 2-year CSP timeframe. Toyota identified that there are roughly 118,950 2012-2014 model year prius V with a production period of late September 2010 to mid-November 2014 vehicles that this faulty part affects along with everyone else on the road with these vehicles as it causes failure of the brake booster pump assembly, which leads to a loss of braking assist and the deactivation of the Vehicle Stability Control system. For the safety and lives of the owners of these vehicles and all of the other lives of the drivers on the road that this could affect in the case of this faulty part should there be a catastrophic accident, like mine could have been, a nationwide recall on this part MUST be issued.

Filed Jan 17, 2025 · Brakes · CA

The issue is my brakes failed on me all of a sudden. My abs light, traction control light, and brake light came on out of nowhere. Suddenly didn't have brake pressure. Had to pump the brakes a few times before the car would stop. Luckily I didn't hit anything or anyone. I brought the car to Prius specialist and they diagnosed it saying it was the ABS Actuator Pump Assembly and Master Cylinder. They said it is quite common in the 3rd generation of Prius'. I contacted Toyota North America and they said they had a recall on the parts but it ended Dec 31st, 2021. I bought the car in 2022 unknowingly. Was quoted around $4000 to repair it parts and labor. This is a safety issue that should not be limited to time. Luckily I was not on a Freeway or anywhere where I could have done damage. This issue is a hazard to myself and other people on the road. Toyota needs to resolve this.

Filed Jul 6, 2024 · Brakes · GA

2012 Toyota Prius brake actuator failure . While driving my Toyota Prius the braking system failed, this was on a large road and so posed a major danger to not only me, but the passengers in the vehicle and the vehicles around us. Thankfully nobody was hurt. After having the vehicle inspected by a Toyota dealership the problem was found to be the “Actuator/accumulator” and after speaking with the dealership it has come to be my understanding that this is a common and unavoidable problem with Toyota Prius models. There were no lights or warnings on in the vehicle until after the brakes gave out. I cannot understand why this has not been recalled when it is a manufacturing issue on Toyotas end that poses a significant danger on the roads, and am wondering what the reimbursement policy for this is as it came out to be quite expensive.

Filed May 25, 2024 · Brakes · IA

Complete Brake failure, confirmed brake accumulator / actuator failure resulting in near miss crash, tow home not drivable, onle e brake works, appears pump burned up not running any longer.

Filed Mar 6, 2024 · Brakes · FL

Brake failure resulting in code C1391. Petition for Defect Investigation dated 09/09/23 summitted to the federal safety agency Office of Defects Investigation via Certified Mail. Received by Office of Defects Investigation on 10/10/23.

Filed Dec 5, 2023 · Brakes · NC

Coming to a yellow light, I braked and the vehicle made a strange sound with loss of braking, so I sped up instead, having to go through a red light. Shortly after, that afternoon, when I again started the vehicle, the safety lights lit up in the dashboard and my vehicle kept making a strange cycling noise. As it turns out, it was the whole brake actuator assembly. Under great financial hardship, I had the vehicle repaired ($4300+). I applied to Toyota Corporate for help but they denied it, saying I was outside the extended warranty. I’ve since learned this brake problem was a known issue, and Toyota settled a class action settlement. My vehicle has only 90,000 miles on it, and it is has been used primarily as an in-town vehicle, our only car. I’m asking for a recall and reimbursement on repair for affected vehicles. Toyota has been allowed to get away with responsibility for a known issue by putting it into a extended warranty program, now expired. Meanwhile, this dangerous, known defect continues to happen to unsuspecting drivers. I was lucky with my incident, as no cars came out when the light changed, but it could have been a different outcome.

Filed Sep 5, 2023 · Brakes · CA

My Prius V experienced brake failure today, with three warning lights appearing at once and the brake pedal not engaging the brakes unless it was pressed almost to the floor. This made it feel extremely scary and unsafe to drive. I was very upset to see that this is a recurring problem with Prius cars in this age range. Although I only have less than 120,000 miles on it, Toyota is not offering an extended warranty for the failing parts (brake master cylinder and actuator and booster) past 10 years or 150,000 miles. This is total BS if they already know that there is a problem with these parts.

Filed Aug 6, 2023 · Brakes · UT

In July of 2021 the Toyota dealership replaced the inverter on my 2012 Prius V. At the time, it also was exhibiting signs of the brake booster and pump failure as outlined in CSP 20TE07 (see https://www.toyoheadquarters.com/threads/2012-2014-toyota-prius-v-2015-toyota-prius-v-coverage-for-brake-booster-and-brake-booster-pump-assemblies-csp-20te07.2116/). It was inside the extended warranty period, but they would not fix it at the time, because it was not throwing diagnostic codes. Subsequently, the braking system malfunctioned, nearly causing a high-speed accident on the freeway. With diagnostic lights now showing, and code C1391 stored in the OBD system, I took the car back to the dealer, but now they said it was past the 10 year limit and still would do nothing about it. This is not acceptable! They knew the brake system was failing and a safety hazard, but would not address it, just because it hadn't actually failed yet. Toyota needs to further extend the warranty and take care of this brake failure past 10 years and 150,000 miles. Just because I took good care of my car and the brakes didn't fail as early as other owners, I should not have been subjected to the risk of brake failure or the high cost of repairing the brake system when Toyota took care of this problem for so many other hybrid owners. Please help.

Filed Jun 22, 2023 · Brakes · 166,000 miles · FL

The contact owns a 2012 Toyota Prius V. The contact stated that while her husband was driving at an undisclosed speed into the dealer's parking lot, the brakes failed to stop the vehicle immediately. The brakes, ABS, and several other unknown warning lights were illuminated. The contact's husband then shifted the transmission into neutral (N) and coasted until the vehicle came to a complete stop. The dealer diagnosed the vehicle with DTC codes: C1252, C1253, and C1256, and determined that the brake booster and ABS pump needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 166,000.

Filed May 12, 2023 · Brakes · 138,278 miles · SC

Failure of hydraulic power brake booster and brake booster pump caused loss of brake fluid resulting in brakes not working properly. Cycling noise from brake booster. Vehicle regenerative brake system also failed to operate. Independent dealer repaired vehicle at my expense after Toyota denied warranty repair