When I try to brake, occasionally, the car jumps forward, instead of stopping. It moves like 6 inches to 12 inches. It happens more often when I try to brake at a stop sign, when the road is rough, or there is a pothole. It gives a feeling of that car actually accelerated instead of slowing, and feels unsafe.

- Belle Mead, NJ, USA

This has happened atleast 4 times in the last year, where the car has lost complete braking power and at the time this happens, all the lights on the dashboard light up for a few seconds and on subsequent pumping of the brake pedal, the brake power returns to normal. On one occasion I almost ended up in the middle of an intersection, thankfully there was no oncoming traffic and was able to recover without getting crashed into. I see a lot of similar complaints here and on Toyota's own community portal describing the exact same behavior. In all cases, the dealership has ended up replacing the brake booster assembly. In my case though, the dealer confirmed that my car was on the recall list for the brake booster assembly, but when they ran some diagnostics tests advised by Toyota which did not report any issues and therefore refused to change the brake booster assembly. I also contacted Toyota (case# [xxx]) only to be told a wishy washy answer. I was told that Toyota cannot do anything about it since it has given guidelines to the dealership and if the dealership says "no" then so does "Toyota". not to mention having spent hours on the phone with Toyota only to be tossed several times between different supports reps and the dealership. Additionally, I was told by the dealership to keep driving the car and see if it was to happen more often. Once it gets to a point where I can find a pattern and reproduce the error with the Toyota rep that's then they will look into the issue. For some reason they fail to understand that I am not complaining about my wiper blades not working but the brakes, which could put the diver in a life threatening situation. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Santa Clara, CA, USA

The contact owns a 2010 Toyota Prius. The contact stated that the ABS and anti-skid warning lamps illuminated while the contact was driving 40 mph. The brake pedal was depressed however, the brakes failed. The emergency brake was used to stop the vehicle. The vehicle was taken to the dealer and diagnosed as brake failure. The master cylinder and the brake booster assembly were replaced. The manufacturer was made aware of the failure. The approximate failure mileage was 50,000. Updated 8/26/13 the consumer stated Toyota admitted to installing a faulty brake pump. The consumer is seeking reimbursement. The consumer referenced recall # 13V235000. Updated 09/10/13

- Louisville, KY, USA

On 6-18-13 at 9:45 am, at NJ turn-pike South, milestone 108.3, newark, NJ. I, owner of the Toyota Prius 201, driving at 45 mph pushed the brake pedal to the floor to stop but could not. I hit the back of the vehicle front of me suddenly stopped. My 2010 Prius was total lost in this accident. According to the Toyota 6-4-13 recall announcement, my 2010 Prius in the recall list is equipped with a brake pressure accumulator that may develop a fatigue crack on an internal part due to vibration that caused my failure to stop completely in this car rear-end collision accident on 6-18-13.

- Fort Lee, NJ, USA

The contact owns a 2010 Toyota Prius. The contact stated that while driving approximately 35 mph, the brakes would not respond. The vehicle was taken to the dealer for diagnosis. The technician stated that nitrogen gas was leaking into the brake fluid. There was a recall under NHTSA campaign number: 13V235000 (service brakes) that could have been related to the failure. The manufacturer was made aware of the failure and stated that the VIN was not included in the recall. The vehicle was not repaired. The approximate failure mileage was 46,000.

- Hunington Beach, CA, USA

As we were driving the car down a hill we began to feel a jerking in the brakes. As we drove onto the ramp to the highway, warning lights and a buzzer went off and the brakes failed. Every 15-30 seconds my husband, who was driving my car at the time, said he had a little bit of braking for a couple seconds, and then he didn't have any brakes again.

- Middletown, OH, USA

Since purchase of vehicle when stopping vehicle, as approaching a stop sign or stopped traffic, if I hit a small bump in road, the car jumps forward. I have not hit another car yet but feel this jump when stepping on brakes whether in dry or wet weather could one day hit car in front of me. This is intermittant. Did mention to dealer when car was for it's timely services. Dealer says there is no recalls.

- Magnolia, DE, USA

Slowly passed over a speed bump, which caused a brief sensation of acceleration (common in this Prius). Then braking was significantly affected, with brake travel quite long and stopping power diminished. All brakes warning lights came on and stayed on. Problem continued until I stopped the car and turned it off. When car turned on, warning lights remained but went out after depressing brake. Took to dealership. Told that brake booster pump needs to be replaced. VIN is outside the range given by Toyota for recall published on 6/5/13. However, symptoms are identical for this vehicle. I'm concerned that Toyota may not be including all vehicles that are affected by this problem in its recall plans.

- Glen Ellyn, IL, USA

The contact owns a 2010 Toyota Prius. The contact stated the brakes failed to engage while driving 55 mph on an exit ramp. The vehicle eventually stopped by depressing the brake pedal with force. The vehicle was driven to the dealer for diagnostic testing which confirmed that the brake power booster pump was leaking internally. The manufacturer advised that the vehicle was not included in the NHTSA recall campaign number 13V235000 (service brakes). The vehicle was not repaired. The failure and current mileage was 46,000.

- Mystic , CT, USA

When hitting larger size potholes or bumps in the road I lose control of what feels like the rear end, its as if the vehicle brakes gives way when the rear tires hit the object, car shimmies slightly, the brakes stop working for at least 3 seconds as the car lurches forward. The brake also depresses further to the floor while it happens. There's a particular spot on my way to work that continues to cause the problem. Its heading down a small declining hill before a turn to the left. If I were to tailgate someone and have that happen I would surely hit them because there's no control of the vehicle for a few seconds after hitting the object. This object goes straight across the 2 lanes as if the concrete paving was poured too high in a long horizontal line. I think it has to be above a 4-5 inches or so because I'll hit smaller ones and I'm fine and I've tested it on different objects, its higher raised items causing the behavior. It happens when its dry, wet or icy out, but you have to be applying the brake to really feel it as far as I can tell. My passenger also felt the loss in control each time this has happened and its been numerous since owning the vehicle.

- Attleboro, MA, USA

For the entire time that I've owned the 2010 Prius, the car lurches ahead virtually every time I run over a pothole with the brakes applied (I.e., approaching a stop sign). When I mentioned this at one of my first appointments, I was assured there was nothing wrong. Now the problem continues and I've been reading that many other people have the same issue.

- Des Moines, IA, USA

I have previously (2010 or 2011) filed a detailed report of the consistent anomaly that occurs while braking on a rough surface or upon hitting a pothole, manhole cover, etc. In this situation, the feedback from the vehicle suggests that the brakes have disengaged. Based upon 2+ years of additional experience, I would note that: (1) this anomaly occurs consistently, and it has not disappeared or attenuated, (2) I believe that stopping distances are longer than would be expected without this anomaly, (3) my Prius was manufactured after the 2010 software fix, and (4) other drivers of 2010 and later Prius cars have reported the same phenomenon when I asked about it (see below). Most importantly, I would note the following source of evidence which you might easily pursue further. I have been living in New York city (nyc) for most of the last two years. The nyc taxi fleet includes a sizable number of Toyota Prius cars. Every time I take a Prius taxi, I ask the driver if he has encountered a similar problem when braking on rough surfaces. In more than a dozen such instances, drivers have consistently reported this same problem. While you may not want to trust my evidence on this matter, it would be very cheap for NHTSA to send an investigator to some of the large taxi garages in nyc to interview drivers with experience driving Prius taxi cabs. Given the large number of miles logged by taxi drivers, this could be an important source of information from highly experienced drivers --- who must regularly contend with nyc's myriad potholes. I would finally note that --- other than this anomaly --- I love my Prius. It is a great car. I would just like for Toyota to figure our what is causing this anomaly and fix it.

- New York, NY, USA

The contact owns a 2010 Toyota Prius. The contact stated that while driving 30 mph, the brake and traction control warning lights illuminated. The vehicle became difficult to stop when the brakes were applied. The vehicle was towed to the dealer for diagnosis and the contact was informed that the brake booster pump assembly would need to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The failure mileage was 39,001 and the current mileage was unknown.

- Chula Vista, CA, USA

I'm a owner of a 2010 Toyota Prius. I almost crash into another car, due to the brake system of this vehicle. I had to drive off the road pavement to avoid the car accident. I had multiple times near miss car accidents before reporting this issue. Due to the very poor braking system on this vehicle. The brake response is very poor. In a quick reaction for braking, this car's brakes will not stop in time to avoid accident. After a recent close car accident 6/3/2013, I have to give a lot of distance between my car and other cars for braking in time to avoid a car accident. As a buyer purchasing a new car, the braking system is a number one priority for safety for a family owned car. I purchase this car for a fuel gas saving car, but it's scary driving this vehicle. Due to very poor brake system in this 2010 Toyota Prius. Toyota company needs to recall the braking systems for all 2010 Toyota Prius. It's needs to be checked and fix for better braking quality. I want to sell my 2010 Toyota Prius, due to this issue of braking, but I can't sell this car due to I still have to pay off my auto loan. My family fears for my safety and other Toyota Prius owners out there. Please someone look into this matter. I fear for my family's safety due to this problem. [xxx] information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Visalia, CA, USA

The contact owns a 2010 Toyota Prius. The contact stated that while driving 35 mph, the contact applied the brakes then the pedal went to the floor and the vehicle failed to stop. The contact pumped the pedal and eventually the vehicle stopped. The vehicle was taken to a dealer where the contact was informed that the brakes needed to be replaced. Several days later the failure recurred. The vehicle was returned to the dealer and the contact was informed that the master cylinder and the brake booster would need to be replaced. The vehicle was repaired. The manufacturer had not been notified of the failure. The failure and current mileage was 144,000.

- Columbiana, OH, USA

The vehicle has a nasty habit of losing brake pressure over bumps. This can be duplicated easily and is a known issue that Toyota has yet to rectify. Simply drive over a bump such as a break in concrete on a bridge, pothole, etc. And hold on tight. This can result in a crash and serious injury as occupants experience a sudden loss of braking force which can induce panic and collision.

- St. Charles, MO, USA

In the past (starting at 2,800 miles) and reported numerous times to the dealer (huntington Toyota), Toyota corporate and the NHTSA, whenever the car went over a rough road service while braking at about 10 miles an hour the regenerative braking would cut out and give the sensation of the car surging forward requiring much greater braking effort to bring the car to a stop. The brakes would reset after a full stop and they would act normally until the next time braking was done on a rough road surface. Toyota claimed that this was normal behavior for the Prius ABS system, even after the firmware upgrade was applied. This time the brakes did not reset after a full stop and every warning light on the dashboard lit up. There was no regenerative braking available. The car was brought to the dealer who has had it for more than a week, and is replacing major brake system components under my extended warranty. I was told that without the warranty these repairs would have cost me over $4500. This has been an ongoing and dangerous situation, which may be finally resolved after all of the brake component replacements. As an aside, the brake pads show significant and unusual wear because the regenerative braking did not work as it should.

- Centerport, NY, USA

Brakes failed while driving. Pedal went to the floor. Very little braking power left. Luckily I didn't have to stop suddenly and was able to bring the car to a stop slowly. Had the car towed to Toyota dealer where they diagnosed the problem as the brake booster / master cylinder. They told me there was air in the brake system. I received a quote for almost $2900 to fix the brakes. I called Toyota corporate office and asked for assistance with this catastrophic brake failure but was refused. Searching online found others with same failure. In particular, there was a person with 43K miles with exact same issue, and Toyota refused to help him. This is a very dangerous failure and should be a recall. Please investigate fully and feel free to contact me for any assistance. I am in the process of replacing the brake booster but I will keep the old one in case you need it for your investigation. I had similar issue on my 2004 Lexus RX330 and there was eventually a recall for it. It is unacceptable for a 3 year old car to have this kind of a safety failure. My wife and kids could have been seriously hurt or killed.

- Valencia, CA, USA

First incident: April 15, 2013 I lost my brakes while I was driving home from my night shift work as a registered nurse. I was at an intersection two blocks from my house when I felt the brake was failing. It was a good thing that I was driving slow to make a turn when I felt the brake system was not working. I was able to steer it to a parking lot nearby by using the foot brake. Prior to this incident, I heard squeaking noises for about three days whenever I step on the brakes. I was relieved that I did not get into an accident. Action after the 1st incident: April 24, 2010. We towed the car to dch Toyota freehold, and it took about 5 days to repair the brakes so they gave us a loaner car which we truly appreciate. But when we picked up the car, the brakes were fixed but the squeaking noise is still present, and our windshield was cracked. We called the dealership right away to inform them about the squeaking noise and to complain about the cracked windshield. I was told by the service representative that their technicians tested my car and deemed it safe to drive and that they would never release my car unless they know it is safe to be on the road. Second incident: April 29, 2013, I lost the brakes again while I was on my way to work around 7:00 pm. I really got very scared because there was so much traffic at that time. I was able to stop and park my car slowly to the curb without hitting anybody else by using the foot break. Action after the second incident: Same night, we towed the car back to the dealership for repair, and after a week of waiting, they finally came back to us specifying that the whole master cylinder and brake pad assembly is defective and needs to be replaced and will cost more than 4K for parts alone. Contacted Toyota about this issue, and they said that they will not assist us, since we exceeded the warranty period.

- Monroe, NJ, USA

On 01 May 2013, I was driving my two daughters home from school and the brakes on my 2010 Toyota Prius failed. The brake pedal became very stiff and the brakes did not respond. I began to panic because we were traveling down a steep hill. I continued to pump the brakes and suddenly, the pedal gave way and the car came to a screeching halt. I was luckily within walking distance of my house. I had my car towed to the dealership and they informed me that my brake booster and master cylinder needed replacement at a cost of $5500. I'm shocked. My car is 3 years old. After research, I discovered this is a common problem for the 2010 Prius. What I find most disturbing is this is clearly a manufacturer's defect, that is an extremely dangerous safety hazard. Prior to owning my Prius, I was a loyal Toyota buyer. I have had consistent acceleration issues with my brakes, even after the recall. If Toyota does not address this issue, I don't intend to purchase another Toyota product.

- Kapolei, HI, USA