The braking system malfunctioned resulting in loss of braking ability and response along with various warning lights including ABS, Brake, and Traction Control. The vehicle produced a C1391 Diagnostic Trouble Code (DTC) indicating "abnormal leak of accumulator pressure." After taking the vehicle to a local Toyota dealer, I discovered there was a voluntary customer support program to replace what was known to be defective brake booster parts that expired in 2020. I previously did not receive any notification about the issue and am now told it will cost thousands of dollars to replace the brake booster parts known to be defective. I now have a vehicle that is unsafe to drive unless I spend an exorbitant amount of money to replace the aforementioned parts.

- Folsom, CA, USA

The ABS, Brake, and traction control light came on. The braking became difficult. The car did stop but if it was in an emergency circumstance there may have been a collision. I called Toyota about the issue and was informed that there was a brake actuater and master cylinder issues with this make and model. Toyota replaced them in cars that had this issue under a special warranty that was over in 2021. It is a $3500 issue. I purchased this car new and have never received a notice about bad braking system. I have lived at the same address since the purchase. Toyota informed me that notices were not sent out, however if the owner came in with this issue before 2021 it would have been repaired and replaced. I can not understand how ALL owners were not informed. I do not understand how a recall wasn't enforced. I live in Florida where the speed limit is 70mph. This could have been deadly. I looked on forums online and apparently this has been an issue for many many 2010 Toyota Prius. I have a case in with Toyota American. 220701001489. I can use any help I can get with this issue. It may save a life.

- Venice, FL, USA

The brakes ABS stopped working. It is a known issue and is effecting many older Prius drivers.

- Longmont, CO, USA

The contact owns a 2010 Toyota Prius. The contact stated while driver was driving 65 MPH and depressing the brake pedal, multiple times, the vehicle brakes failed to stop the vehicle within a reasonable time. The contact stated there were several unknown warning lights illuminated simultaneously. The driver was able to slow the vehicle using the parking brake and driving onto the grass on the side of the road. The driver was able to continue driving to the local dealer. The vehicle was diagnosed and the contact was informed that the braking system needed to be replaced. The vehicle was not repaired. Upon investigation, the contact associated the failure with NHTSA Campaign Number: 13V235000 (Service Brakes) however, the VIN was not included. The manufacturer had been informed of the failure. The failure mileage was 179,747.

- Alamo, TX, USA

Brake booster failed. Brake Actuator failed. ABS, BRAKE and TRACTION control light is on.

- Lorton, VA, USA

I purchased my car in January 2010 within that first year I noticed that randomly if I hit a bump in the road and I would apply my brakes my car would do a wired skid and I couldn-??t break properly. This has continued the entire time I-??ve owned my car. Last month I was driving down the highway and ABS! Red brake light and ABS warning light all illuminated. As I was exiting the highway and applying the break I noticed my brakes were very spongy taking considerably more effort to stop. I started noticing a few months ago my breaks took considerably more effort stop and breaks felt spongier. The day my warning lights lit up a mechanic stated a code of C1391 was detected. Indicating break booster problems. NHTSA issued a recall Rep 13v235000 which is Break Booster my car was manufactured 10/09 so I understood my car was part of this recall but Toyota claims that is not a recall but a customer support program which has expired 2 years ago. I-??m the original owner w/ 69,000 miles. Clearly my vehicle has and continues to have break issues so why is Toyota shirking responsibility and endangering me and other drivers allowing a car w/ breaking issues to not be properly repaired under the recall

- Chandler , AZ, USA

I believe Brake Actuator seems to be malfunctioning. Noises come from the location of the Brake Actuator when I am lightly braking at low speeds. I am getting Antilock Braking System code "C1256" reading "ACCumulator Low Pressure". There are a similar recalls related to my issue. Recall number: 10V039000 and Recall number: 13V235000

- Taylors, SC, USA

Brake booster/ Brake Actuator problems

- Kyle, TX, USA

A known defect was briefly recalled, then sunsetted. My brake attenuator has failed, as has been the case for many others on this model. Toyota has acknowledged the defect, but no longer supports it.

- Los Angeles, CA, USA

Normal braking pressure failed to stop the vehicle requiring the driver to apply very heavy pressure to stop the vehicle and avoid a rear end collision. Multiple dash lights appeared and the vehicle was towed to a Toyota dealer. The dealer confirmed codes C1252 and C1256 exist and recommended that the brake booster pump assembly be replaced. An August 6, 2018 Toyota Service Bulletin (T-SB-0079-18) recognized this problem. Toyota sent Customer Support Program Notification ZJB noting that "Toyota has received reports about certain internal malfunctions of brake booster assemblies in some of the subject vehicles. In these reports, customers have noted various brake system related warning lamps illuminated." Toyota noted that, "This is not a recall." Toyota suggests that certain warning lights may illuminate but does not warn drivers that normal braking may cease and that the vehicle can be dangerously difficult to stop.

- Monument, CO, USA

ABS brake light on. Just purchased this vehicle and found Toyota knows of a defect in the master brake cylinder that causes it to leak. Toyota was repairing this problem free of charge till 2019. This vehicle has never had the repair. I am told brakes may go from power brakes to non power brakes while driving. We are not driving till it gets fixed because of safety problem with brakes.

- Glen Carbon, IL, USA

There is a known problem with 2010-2015 Toyota Prius brake actuator assembly and also the brake booster pump assembly. A leak develops and cannot hold proper brake pressure which will lead to catastrophic failure of the system and a life or death brake failure. Toyota has acknowledged the problem and issued a recall only covering 150,000 miles or 10 years from date of first use. This recall should be extended to all affected vehicles for the LIFETIME of the vehicle given that it is a known manufacturing defect affecting life and limb and that repair costs average over $3000.

- Waialua, HI, USA

Brake booster/ brake pump / accumulator sudden failure BELIEVED TO BE CAUSED BY THE SENSOR WARNING SYSTEM -??? THAT ABS LIGHT ASSOOCIATED WITH CONSTANT BEEPING NOISE, 10 SECONDS LATER LOSE OF BRAKE POWER. factory trick to get brake service, at large for this repair costs 3800 per dealership toyota carlsbads. Manipulative recall ???" disallowed me on 3 occasions unable to get part replaced by Toyota. When contacting corporate the did not demand me to get fixed and not drive NY car, again getting my car to tge service station experienced noise occurring then sudden outage of brake power reduced to nothing. A similar youtube video and my personal video explain sudden loss of brake power or pressure... after lights go on. And immediately return to normal after lights get reset. Sensor failure leading to brake failure, really scary and obviously a big problem TOYOT SHOULD STILL BE RESPONSIBLE FOR. CONSUMER SERVICE PROGRAM BY TOYOTA FOR THIS BRALE BOOSTER ISSUE STOPPED FOR SOME REASON IN 2019 ALSO. 150K BS RULE. MERCEDES BENZ HAS TAKEN THE RIGHT ACTION TO FIXING BRAKE BOOSTER ISSUES.

- Vista, CA, USA

Hi- I have a Toyota Prius 2010 model and I encountered a braking failure yesterday. My ABS lights, brake lights and another light came up on my dashboard of the car. Upon diagnosis, I was informed by Toyota dealership that my car has a faulty C1391 - Abnormal leak in accumulator. This condition may be caused by small internal brake fluid leak inside the brake booster assembly with master cylinder. This is a known issue by Toyota and lots of press coverage on this issue since the past few years. I was told today that if this issue occurred within 10 year or purchase or <150K then the repair work would be covered by Toyota. I purchased the car in 2010 and I past the 10 year mark but mileage coverage is 125K (<150K). Toyota is unwilling to bear the cost and would want me to pay for the fix. This is a known issue with Toyota and the braking system can fail anytime before/or after 10 year mark. It is now costing me $3000 to repair. I am shocked with the Toyota's response in this matter. There are lots of blogs I read online who have similar issue. Class Action lawsuit: https://www.classaction.org/news/toyota-hit-with-class-action-over-alleged-refusal-to-fix-braking-system-defect-in-hybrid-vehicles Here is one example: https://www.youtube.com/watch?v=xA9jyrbZDWo Thanks.

- Manvel, TX, USA

The Traction control, ABS, and Brake light all came on simultaneously. It was random with no trigger. The brakes feel spongy, and will not regenerate to charge the hybrid system.

- Clarksville, TN, USA

My brakes have been making hissing noises whenever I press on the brake pedal for the past year. While driving on the freeway 300 miles from my home, numerous lights on my dashboard came on including brake, VSC, PCS, ABS, Triangle and "CHECK PCS SYSTEM" warning message. The brake also makes pumping noise every 4 seconds. The vehicle has no regenerative braking. The brake pedal is mushy and doesn't slow the car down until the pedal is fully depressed. I contacted Toyota and was told that there was a Customer Support Program ZJB that covers 2010-2015 Prius Vehicles for Brake Booster and Brake Booster Pump Assemblies. However, that program only covers 10 yrs 150 miles. My Prius has 110k miles but it's 21 months passed the program coverage. The car is dangerous to drive and Toyota will not honor the recall. I am stuck with a car with no brakes.

- Bakersfield, CA, USA

On March 25, 2022, I was driving my 2010 Toyota Prius, approx. 209,000 miles. When I had parked my vehicle, and turned my A/C on, my vehicle started to make this annoying beeping noise non-stop and all of the light on the dashboard had lit up. My brake lights, ABS, and the slip indicator all came on. When I went to drive my vehicle all of sudden my brakes did not respond. I had to force break and push down on the brakes very hard, to the point where I'm flooring the brakes. I checked with Toyota to see if there was a recall on my vehicle, and they told me that there were no recalls. When I did my research on 2010 Toyota Prius, I found that this is a common issue that the brake actuator and brake booster pumps are faulty on these vehicles. I did not receive a recall notice for this vehicle. Currently, my vehicle is not drivable and not safe to drive. For this to happen out of nowhere with no warning is unacceptable.

- Green Valley, AZ, USA

As nitrogen is released into the brake fluid, the brake pedal may have reduced hydraulic pressure. Under certain circumstances, this condition could affect stopping distance and increase the risk of a crash.

- Moreno Valley, CA, USA

A number of things have failed on this car. 1. The hybrid battery pack system shut down and warned that I needed to see a mechanic. My mechanic diagnosed that the hybrid invert was defective and causing the battery pack to fail. 2. When braking at both low and high speeds, the car increasingly struggles to come to a stop. When applying foot pressure, you can hear the pump winding - this occurs while at rest as well as when trying to slow the car down. There are times when applying the brake that the floor pedal will lock and cause the car to skid while barely reducing the speed of the car. I have had multiple near accident incidences as a result and put myself and others at risk. 3. The car ferociously vibrates every morning - discovered that the head gasket has failed prematurely and due to the car overcompensating for the failing hybrid battery that is being impacted by the failing hybrid inverter. All problems have been reproduced and diagnosed at independent service centers. Multiple codes, warning lights and messages have alerted me to engine and battery issues - all of which appeared after the various issues and failures.

- San Francisco, CA, USA

2010 Prius Brake, ABS, Traction Control Lights On/Off with no codes I bought new car and running smooth so far. I got this lights 2 months back and off for sometime and came back on and off and now quite often coming back and forth, 106K miles had the ABS, Traction Control and Brake light all come on at once same time and off same time and back and forth. No codes and no flashing but this is very critical as all related to brake systems failures may leads to crash because we don't know when this lights on and off and no codes to fix this issue.

- Plymouth, MN, USA