The contact owns a 2012 Toyota Prius. The contact stated while driving 50 MPH and depressing the brake pedal, the vehicle failed to respond. The vehicle responded after depressing the brake pedal several times, and came into a complete stop. The ABS and anti-skid warning light were illuminated, and the message "Brake" was displayed. The vehicle was taken to an unknown location, where it was diagnosed that the rear passenger brake sensor needed to be replaced. The vehicle was repaired; however, the failure reoccurred. The vehicle was taken to an independent mechanic, where it was diagnosed that the pump actuator needed to be replaced. The vehicle was not repaired. The mechanic referred the contact to the manufacturer. There was no further information provided. The manufacturer was contacted and informed the contact that the vehicle could not be repaired under an unknown Technical Service Bulletin Number as it had exceeded the mileage and year required. The failure mileage was 165,000.

- Mahopac, NY, USA

Driving on Interstate and suddenly traction control light, brake Light, and ABS light came on. After this the brakes were not as affective at stopping the vehicle and felt sluggish. Found a lot of reports online about similar issue and even some when the vehicle brakes failed. My brakes allowed me to get home without incident.

- Birmingham, AL, USA

Our 2012 Toyota Prius experienced brake failure due to the Accuator and Accumulator. I contacted Toyota Corporate office, which advised it is a known problem and had a customer support program that expired last year. The Toyota rep advised me to not drive the vehicle because of the brake failure and opened a ticket advising it is a known issue. After researching online, it is a very common issue. https://www.aboutautomobile.com/Consumer-Complaint/2010/Toyota/Prius/Brake

- Mt. Washington, KY, USA

Suspected Brake Booster failure. We have been experiencing our brake booster running several times a minute and something felt off. In December, we took it to the dealership who said they "were unable to replicate the issue". We found that odd since we experience the issue every few minutes, but we believed them when they said that there was nothing wrong with our brakes. Yesterday, about one month later, we were driving on a busy street when our brakes appeared to fail. We couldn't make the car stop, three dashboard lights came on (the ABS and two others) and eventually we realized the brakes had to be pressed really hard to get the car to stop. We avoided an accident, pulled into a parking lot, turned off the car, checked the brake fluid (the brake fluid was fine), restarted the car and the lights still remained and the brakes continued to not compress easily. We called our Toyota dealer who said that there is no recall on our Brake Booster and that this is not a known issue, and yet there are hundreds of readily available accounts of 2012 prius owners who experience the same fail.

- Greensboro, NC, USA

Toyota Program ZJB, internal malfunctions of the brake booster assemblies. A known failure of the brake booster than Toyota did extend the warranty on for 10 years BUT would not honor the warranty unless specific diagnostic codes appeared on the vehicle. My issue is that all of the symptoms of the failure occurred on my vehicle (pump constantly running, varying hydraulic pressure resulting in pulsing brake stops, soft brake pedal) but the warranty would not be honored because the diagnostic did not manifest itself. Had technicians tell me that it definitely was this booster failure, but Toyota would not pay for it unless the diagnostic came up. I am now left with a vehicle that has a failed brake system and no monetary support from Toyota. Quoted $2500 to $3000 to repair. Not safe to drive in my opinion with a known failure that I am having trouble getting funding to repair. Contacted Toyota customer support and they reiterated that they would not pay for the repair without the diagnostic occurring and now their extended warranty expired August 31, 2021. Inspection available upon request Safety issue as braking is inconsistent and not predictable Problem was identified by Toyota dealer service department No diagnostic alarms - which is the only symptom not present

- Roanoke, VA, USA

The Brake Booster or Actuator is failing, without any indication or warning lights on the dash alarming us to the problem. The car has been making weird sounds, but after being inspected, this, according to the Authorized Toyota Dealer, on December 22, 2022, is a life-threatening and very dangerous malfunction to myself and others around me when driving. This is the first hybrid car we have owned, and we thought the noises we had been hearing for a couple years was normal, because there were no warning lights coming on to tell us otherwise. The dealer did not want us to drive the car any further due to the danger of the problem. We asked the dealer to repair the problem without charge, but that request was denied by the Toyota Brand Engagement Center (Case 221222000587). The dealer is currently repairing the malfunction at a cost of approximately $2650 plus tax). We are highly disappointed with Toyota not repairing this known problem under a dealer recall.

- Lake Forest, CA, USA

The brakes on my 2012 Toyota Prius failed suddenly with little warning after starting the car, and when I began driving off in a busy Walmart parking. I was startled when I felt that the brakes did not seem to work, nearly causing me to collide with the car in front of me. I had to quickly depress the brake pedal to bring the car to a stop. The normal braking power was greatly reduced when I depressed the brake pedal, and I had to use more force to bring the vehicle to a stop. Only when I looked down did I see that some of the dashboard lights relating to the brake system stayed lit and not turn off like they normally do. These lights appear to be brake warning, ABS warning, and anti-skidding lights. The brake problem has been inspected and confirmed by both an independent service center as well as the Toyota dealer. The failed brake component was diagnosed as an abnormal leak in the accumulator, and the brake booster with master cylinder assembly requiring replacement, with the code #c1391. After having done some research, it appears that this exact brake problem seems to be afflicting many such generation Toyota Prius vehicles, and the manufacturer Toyota was aware of this problem existing in such vehicles.

- Chino Hills, CA, USA

The car has been diagnosed by a Toyota dealership as having an internal leak in the Brake Booster and Accumulator, both are part of the brake system. Repair estimate of $3800 00 dlls. Currently i have 3 check lights on, Brake, ABS and Traction control. All controlled by the same module

- Garden Grove, CA, USA

My prius got ABS, Brake, Traction light on when I was on traffic in the highway. Car lost brake power. Regenerative brake does not. It takes longer to stop the car. TOYOTA NEEDS TO FIX THIS. THE ABS MODULE IS GONNA FAIL AT SOME POINT. Dealership asks $5000 to fix. C1391

- Columbia, TN, USA

At 106K miles and after 10 years and 8 months in service (new vehicle bought in March 2012) Brake booster internal leak, code c1391. Brake light, ABS light and VSC light stay on. Can not drive it as the brake booster internal leak is making the brakes spongy and slow in response. Talked to Toyota and they said it is out of warranty and the deal is estimating $2000 plus for the repair. Miles on my cars 106K are way less than 150,000 allowed by Program Service bulletin ZJB (attached) but Toyota is denying repair coverage as the vehicle life is eight months more than 10 year limit since first use. Did not drive it much within the last two years because of working from home due to covid 19. Had it been driven more frequently the brake system failure would have happened way earlier as the internal leak (possible fatigue failure causing leak) should be more related to driven miles and brake system cycling of pressurizing and depressurizing than just being parked on the drive way. Would request if NHTSA could extend the duration of ZJB bulletin considering the fact that many drivers did not drive that much in the last two years due to working from home and this internal leakage failure can be related to fatigue loading of the hydraulic components and the number of fatigue cycle are directly proportional to the driven miles and not the life of the vehicle. Thanks

- Greer, SC, USA

The brake system (accumulator/booster) has failed and reduced stopping ability. Error code is C1391

- Charlotte, NC, USA

I have a 2012 Toyota Prius that the Toyota dealership has confirmed that I have a failed ABS actuator and is displaying the correct repair codes for the service bulletin but they refusing to cover any of the costs to replace the ABS actuator and boost pump. Since the failure of the ABS actuator I have had 2 close calls where I needed to stop fast and my tires locked up, I lost control of the car and spun out but luckily I did not hit anything. The brake, ABS, and 2 other warning lights have come on and off intermittently on the dashboard of my 2012 Toyota Prius. I summited a good faith request to the repair my Toyota Prius ABS actuator at Toyota of Anaheim on 10/28/2022 and due to it being 20 days past the 10 year limit and slightly over the 150,000 mile limit at 158,000 they say that I'm 100% responsible for the repair costs of $3,231.78. This proven design flaw is not my fault, it did not occur under normal wear and tear and the brake ABS actuator and boost pump should last much longer than it did. Now I'm faced with paying a huge bill for the repair or pick up my Prius from the dealership and drive it home with a defective ABS actuator. This is another example that Toyota is placing profit ahead of safety.

- Brea, CA, USA

During a hard braking, felt brake pedal softer and less responsive braking. Now ABS Icon, Brake Icon, and Traction Icon is on. Confirmed Code P1391 in ABS system.

- Allen, TX, USA

My breakes failed when driving. I almost got in accident. Code C1391. Brake Actuaror Failure. car has 200,000 miles. Toyota is denying to repair the car. It is well known problem with that but still not fixing.

- Brooklyn, NY, USA

While on the freeway, I was braking due to traffic and the car started shaking and the ABS light, "BRAKE" light and traction light all came on and remained on. The brake system did not operate properly, which nearly caused a collision.

- El Cajon, CA, USA

Driving approx 35 MPH. Traction, Brake, ABS lights all illuminated. Went to brake and brakes went almost to floor with little to no braking power. Car felt out of control and unreactive. Slowed down, pumped brakes (brakes worked but not normal) and pulled over. It was extremely scary and happened out of the blue with no warning, I thought I was going to crash as car felt "slippery" and unresponsive/no braking. If there was a red light or someone stopped in front of me, I would have crashed. Tested and found code of C1391 ABS Anti-lock Brake System Abnormal Leak of ACC PRESS. Researched and found customer bulletin from Toyota POL18-03 and Customer Support Program ZJB. Safety at risk - near accident, could have been a huge accident, no warning and no brakes. This should be a recall! No warning lights prior to failure, lit at time of failure. I was completely unaware of the potential brake failures. Toyota should issue a recall or cover repair. I have been tossed back and forth between corporate & local dealer. Customer coverage expired June 29, 2022 for my car (10 yrs after 1st use). The incident occurred barely one month later on August 16, 2022. It is under 150,000 miles. Toyota refusing to assist or take responsibility for repair coverage. I have been given the runaround by Toyota and attempting to get a call from a case manager is near fruitless. One case manager left me a voicemail indicating that they cannot help me until I take the car to a local dealership to diagnose. So I did. Forced to Toyota, we carefully drove on side streets to the dealership only to be charged $130 for diagnosis & attempt to "upsell" extra services. Vehicle inspected by Toyota. C1391 replace brake booster assembly master cylinder and brake pump almost $3,000. We drove home white-knuckled. After many more phone calls and unable to speak to a case manager, I rec'd a voicemail indicating they will not cover due to expired June 29, 2022. Same issue happening w/other models - pls recall.

- Wichita, KS, USA

While commuting home by Prius has the traction control, ABS, brake light, and brake system indicator dash lights activate. I was able to make it to an autoparts store and the code C1391 was displayed. Researching this code points me to a safety issue that Toyota is aware of and their remedy ended in 2021. Toyota should warranty this known issue, especially for those people who were never notified of the failure of the brake accumulator and brake booster. I now am afraid to drive my vehicle due to potential failure of the brake system and the costs of the repairs are really expensive.

- Tyrone, GA, USA

Seven days ago, the hazard lights on our 2012 Prius suddenly would not turn off. By the time we got home, the brake, ABS, and the traction warning lights all came on. Two hours later, the hazard lights stopped blinking but the other lights were still on. We brought the car into the Toyota dealer for service the next morning (8/1/2022) to have the issue checked, notified the service writer of the hazard light being the initial issue. Mechanic cleared the codes and the lights all were off and stayed off after what he said was 2 test drives. We asked him if the mechanic had tested the hazards, to be sure they didn't stay on. He said the mechanic had left and we agreed to leave the car overnight so he could check that again. The service writer gave us a list of other repairs/maintenance we should have done but none of them was the brake booster acuator. We declined the other service and went home. Car drove fine. Yesterday morning, we woke up to see the hazard lights flashing, even though we hadn't egnaged them since the previous Sunday. Our neighbor noted he noticed them flashing at 2 am. We brought the car back to the dealer and when my husband spoke directly with the manager, he (manager) said that they weren't aware of the hazards flashing. That is a lie. I told the service writer when it was brought in and then we discussed it again that afternoon. Manager calls us late yesterday to say that we need to replace the brake booster acuator at the tune of $3400+. The manager told us this morning that Toyota had a recall on it but they weren't notifying people unless the issue occurred. He said there was recall coverage, which Toyota extended, but it expired 7/24/2022. We never received any mail or email notification of a recall and have only had our car serviced at this dealer. Why did they not warn people" We are outraged and livid. How is this kind of greedy chicanery allowed"

- Milton, MA, USA

ABS system has malfunctioned- brakes lose pressure constantly (makes a barking noise when pressing on them or holding them down), and brakes feel very squishy. Car constantly makes whirring noise of actuator pump trying to function. Mechanic said on inspection that it was the abs actuator and potentially the master cylinder as well. Vehicle is unsafe to drive

- Henrico, VA, USA

Faulty brake booster pump

- Homestead, FL, USA