In August of 2024, my 2010 Prius with less than 100,000 miles - all the brake warning lights on the dash suddenly came on - without any prior warning. The brakes felt a little "funny" at the time, so I took it to my mechanic immediately because my safety or the safety of other was at risk if the brakes completely failed. My mechanic informed me that there was a TSB for the brake booster with master cylinder and brake booster pumps that Toyota new about. I felt that it was imperative that this was repaired immediately. Apparently Toyota knew about this issue but did not notify me in any way at any time. I bought this Prius new and have had regular service check ups. I had to pay nearly $5,000 to have this repaired which I feel that Toyota should reimburse me, and any others who had this problem.

- Texarkana, TX, USA

ABS and brake lights lit at around 141000 miles code C1391 came up during diagnosis.

- Hoover, AL, USA

Brakes started making a hissing sound a couple of weeks ago. Yesterday evening when I was driving on freeway, I got an assortment of lights on my dash while driving. ABS was instantly disabled and it was significantly harder to brake the car. BRAKE light on dashboard came on. Traction control light came on. It was very dangerous and it was mere luck that there was no car in the front - otherwise I could have crashed. Pulled over to the side on the freeway and then came in internal roads to my destination, keeping a lot of braking distance and at slow speed. Turns out this is the infamous brake booster leak that was so bad Toyota was forced to create an extended warranty program on Gen 3 to fix it. Brought it to dealer next day. Got an estimate for $4000 for "REPLACE BRAKE BOOSTER AND MASTER CYLINDER(DUE TO INTERNAL LEAK)"

- Santa Clara, CA, USA

Heading westbound on I-70, taking Exit 29 off ramp from highway, I drove over uneven pavement. My traction control, ABS and brake lights illuminated, the brakes suddenly felt mushy. As I approached the stoplight at the end of the exit ramp, I questioned whether I would be able to stop. Scared me immensely. Luckily no cars were near me. I now do not have ABS, Traction Control, stability control OR regenerative braking.

- Englewood, OH, USA

The contact owns a 2010 Toyota Prius. The contact stated that while driving at various speeds and the brake pedal depressed, the vehicle lunged forward. On a most recent occasion, the contact was attempting to park the vehicle and after shifting into the park position, the vehicle lunged forward as the brake pedal was depressed causing a minor collision with a curb and another vehicle. The contact mentioned the brake pedal required excessive force in order to come to a stop and that there was an abnormal noise present. The contact was concerned that the failure would progress causing a severe accident. A police report was not filed and there were no injuries sustained. The vehicle was taken to an independent mechanic where it was diagnosed that the ABS System failed and advised the vehicle be taken to a dealer. The vehicle was not repaired. A dealer was not contacted. The manufacturer was not notified of the failure. The failure mileage was not available.

- Arnold, MD, USA

Toyota refuses to cover a recall that I was never made aware of. My Prius need to have ABS Brake Accumulator and other components replaced. My VIN I was told had a recall but I was never made aware. I was told it may not be safe to drive my car. Toyota told me I would have to cover all cost for the repair and for my family that is just not possible. For the safety of my family, I am hoping NHTSA can help me in anyway.

- Clovis, CA, USA

NHTSA CAMPAIGN ID: 13V235000 Toyota will notify owners, and dealers will replace the affected brake booster pump assemblies. The recall is expected to begin late July 2013. Owners may contact Toyota at 1-800-331-4331. Toyota is no longer honoring this recall. They think it is acceptable for me to drive around with unsafe and defective brakes.

- Charlotte , NC, USA

In 2015 I purchased my Toyota Prius in VA. I now live in Indiana and had my car checked for a possible sensor issue because the traction, brake & abs light were coming on and off. The diagnostic showed a brake accumulator leak malfunction. I contacted Toyota dealership once I was told there was a recall. The dealership said that it was showing it was replaced in 2013 from the previous owner in VA. It was listed then as a recall. I contacted Toyota Corporate and they said that it went from a recall to customer support with a maximum of 150,000 miles. I did not have any more problems until just recent. My argument is once a recall it should still be repaired. The part appears to be the problem. It is a safety issue and I need Toyota to fix the problem. Thank you!

- Corydon, IN, USA

The car suddenly threw a C1391 code yesterday with no previous warning. The traction, parking brake, brake system, and ABS lights are all lit on the dashboard. As this vehicle is my daily commuting vehicle, I must have the costly repairs performed, which are estimated at roughly $2,400. I will ask to retain the parts for inspection. The brakes are softer, and the breaking distance required has increased by approximately fifteen feet.

- Wiggins, MS, USA

The ABS Pump( Accumulator and booster) are regularly failing on all Toyota Prius( 2010-2015). When the ABS pump starts to fail, the warning lights for Traction control, Brake and ABS come on. These lights come on at all speeds and its very hard to bring the vehicle to a complete stop when this happens. The brakes completely stop working and the brakes become rock solid. The brakes become so hard that they can-??t be possibly be depressed to stop in time. I nearly missed getting killed from this as I am out of country and Toyota is refusing to fix it since its not a recall and I am in Canada. Toyota is asking $3500 in parts and $1500 in labor to repair. I can not afford it and this issue is on all Prius from 2010-2015. This is a major safety hazard and can cause serious injury and damage. Toyota is refusing to repair it since they believe the cars are out of warranty. However Toyota has been notified about this safety hazard arising on all Prius(2010-2015) but decline to respond or take action. I urge NHTSA to take action and get this resolved as the ABS brakes failing on the Prius can be really dangerous and can cause life threatening accidents.

- Cleveland, OH, USA

The contact owns a 2010 Toyota Prius. The contact stated while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. In addition, the contact stated that several unknown warning lights were illuminated. The vehicle was taken to an independent mechanic where it was diagnosed with brake system failure. The contact was informed that the braking system needed to be replaced. The vehicle was not repaired. The contact was advised to take the vehicle to the dealer for service. The contact was made aware of Customer Satisfaction Program: C1391. The vehicle was taken to the dealer where the vehicle was diagnosed with brake system failure. The contact was informed that the braking system needed to be replaced. The contact was informed that the repair was not covered under the Customer Satisfaction Program: C1391, because the mileage had been exceeded. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 166,000.

- Dublin, CA, USA

ABS Lights turned on and need replacement. This is my 3rd Prius that have the Issue.

- Clovis, CA, USA

The contact owns a 2010 Toyota Prius. The contact stated while driving at various speeds, the brake pedal would depress to the floorboard initially without warning. Over time, the brake pedal had become stiff upon depression with several warning lights illuminated on the instrument panel. The vehicle was taken to an independent mechanic where a code reader confirmed a defect with the braking system. The vehicle was then taken to another independent mechanic where the vehicle was diagnosed with a defective brake booster. The mechanic then informed the contact of NHTSA Campaign Number: 13V235000 (Service Brakes) which was linked to the failure. The dealer was notified of the failure and informed the contact that the vehicle was not included in the recall. The manufacturer was notified of the failure but offered no assistance. The vehicle was not repaired. The failure mileage was approximately 153,000.

- Independence, MO, USA

Prius Gen III has a known defect with failing Brake booster parts. In Nov 2023, while driving my 2010 Prius (~160K miles), suddenly brake, ABS, Traction control, skid indicator lights popped up on the dashboard and I have lost the ability to brake effectively. There was a brake pressure loss and I had to slam hard the brakes to slow the car. The error code was 'C1391' and the mechanic diagnosed it as failure of Brake booster parts ABS Brake booster pump (accumulator) - part#47070 47060 and Brake master cylinder (actuator), part#47050-47140 and he replaced both these parts. Toyota is aware of these failures which are very frequent and hence they issued a brake booster -??customer service program-?? ZJB - which extended the warranty for these parts. But many of us were not covered by this warranty either because of the time or mileage restrictions. This was a costly repair and we had to fix it out of pocket at the cost of ~$3000 as this is safety hazard without proper braking. To make matters worse, 3 months after the repair, the newly installed parts failed again and I had to go through the same repair. I called to Toyota to complain about this and they cannot do anything about it and advised me to report it to NHTSA.

- San Jose, CA, USA

The contact owns a 2010 Toyota Prius. The contact stated that while driving at 55 MPH, with the brake pedal was depressed and went to the floorboard. The contact stated that the brakes failed to adequately slow the vehicle. The ABS warning light was illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the brake booster. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 13V235000 (Service Brakes) however, the VIN was not included. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The failure mileage was 120,000.

- Chicago, IL, USA

My car accelerated significantly on its own while I was pulling into a parking stall in a private parking lot. It caused my vehicle to jump a curb and accelerate up a dirt divider and push over a bush that was planted in the dirt divider. Depressing my brakes did not Decelerate the car, so I pressed the Park button to eventually stop the vehicle. I-??m not sure what speed it was traveling when it accelerated, but I could smell burning rubber at the end of the incident. I-??m not sure when the smell first occurred.

- Irvine, CA, USA

Brake booster assembly failure. Code C1391 - accumulator pressure leak. Toyota previously agreed to extend the warranty on this part on this year of Toyota Prius due to the known issue and the time limit for this repair was set to be in 2019. Toyota agreed to replace the unit only if it fails before that timeframe. My Toyota got recently affected by this issue resulting in over $3,000 estimate for a repair as Toyota no longer covers this repair for my vehicle. That-??s a known issue with this part, Toyota knows it-??s faulty and yet no recall has been issued. Now I have to pay for a repair out of pocket. I can-??t drive the vehicle until it-??s fixed. This should be handled as a recall with all faulty units being replaced regardless of millage. A few people opened lawsuits on this issue before and some got a settlement. I believe there is enough evidence that this should be classified as a recall and a free of charge repair should be provided to the owners. The brake booster unit has been buzzing a lot for quite a few months ( due to the pressure leak it had to work more than normal). Now it completely failed with the leak being so excessive that the brakes are very soft.

- Grandville, MI, USA

I-??m encountering multiple dash lights with the brakes being very unreliable and no that-??s no regenerative breaking. I checked with an obd2 kit and the app shows that I have a code C1391.

- Long Beach, CA, USA

Faulty brake boosters that crack and leak, making brakes unusable and draining the battery (diagnostic code C1391). There was a Toyota service repair where they exchanged the faulty brake boosters with properly working ones, but it has lapsed.

- Nashville, TN, USA

[XXX] We took in 2010 Prius to Toyota Dealership in Pharr Texas because road hazard light, ABS, Brake and low tire alarm came on while driving car. They ran diagnostic and found out that the brake pump assembly and brake cylinder assembly has to be replaced. We called Toyota Cooperate to ask for assistance to pay for cost and after 4 weeks of reviewing issue they said they could not help us because the CSP had expired. This car was given to us by a friend of ours and they had not used it for 2-3 years so we got it we repaired and got car running again. After we drove it we came across this problem with the brakes. This car was was built in the same plant as the other recalled cars going by by the vehicle number. We believe that the CSP should be extended or changed to a Recall" Will you help us or direct us to whom we can contact with this safety issue" I have the Toyota diagnostic report from Toyota and Toyota Corporate Letter on email. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Mcallen, TX, USA