While I was braking to stop at the red light, the car accelerated. I moved the steering wheel to hit the curb to prevent crossing the red light. It happened to me couple of times. Then I realize it happens only when I am driving over uneven surface or over bumps. It is really scary. I almost hit a car seattle downtown going down the hit because my car accelerated instead of stopping. I took it the car dealer but they said there is no problem. I am afraid that I might get in a big accident.

- Renton, WA, USA

Vehicle surges when brakes are applied while traveling over railroad tracks or rough pavement. Surge lasts for 1 to 2 seconds until braking resumes. Vehicle behavior can be easily replicated.

- Dallas, TX, USA

The brake booster pump began running continuously when the vehicle was on. Warning lights on the dash indicated brake failure and anti-lock system failure. After I took the vehicle to a Toyota dealer, they determined that the brake master cylinder/anti-lock assembly had failed. The repair took two weeks and cost $3000.

- Burien, WA, USA

I was driving to work this morning and a man stepped off the curb right in front of me (not in a crosswalk). I hit my brakes, and hit a pothole in the road at the same time. The car accelerated and felt as if it was shuddering, it was not braking at all even though I mashed the pedal to the floor. I was forced to swerve to miss the man, which I thankfully did. After that I got moving again I applied the brakes and they worked fine. When I arrived at work I tried it again by finding some potholes in the parking lot. @ 15 mph the problem occurred again only when I was hitting the potholes while applying the brakes. I went to Toyota.com and found this has been an issue since Feb 2010. I purchased my car in Nov 2010; I then called my service dealer and talked to the service manager who claimed to have never heard of that problem even though I told him I found the info at the pressroom.Toyota.com website. He then proceeded to let me know I should not believe everything I read in the internet and offered to let me bring it in and he will look at it. I am leaving work early today to have it looked at.

- Gloucester, VA, USA

Multiplie incidents: We will be driving the vehicle and hit a bump / pot hole and be braking, but the car will accelerate.

- Plymouth, MN, USA

In the morning I started my car and the ABS light and warning lights came on and started beeping. I reversed my car slightly to check the brakes and noticed my brakes were not being responsive. I put the vehicle into park and called the wondries Toyota dealership and told them my brakes were not functioning properly and my ABS warning light was on. Despite my having informed them of my brake failure, they told me to bring the car into the dealership. I reversed out of my garage, shifted the car into drive, and proceeded down the hill with caution. I did not press on the accelerator. My car began to accelerate down the hill due to gravity and reached a speed of approximately 15 mph, at which time I pumped the brake pedal but the car would not stop or slow down, and it continued moving down the hill. At the bottom of the hill, after traveling approximately 1/4 of a mile, I turned right into a small street with a slight incline in order to stop the momentum. My car slowed and I put on the emergency brake and put the car into park. I called my brother for help. When he arrived, I turned the car on to show him the flashing ABS warning. It flashed for about another 15 seconds before suddenly stopping. My brakes then began functioning again though they felt spongy when I pressed down on it. I turned on my emergency lights and drove slowly to the dealership. I parked the car and turned off the engine. When a representative came by, I turned on the car and she pressed down on the brake to feel them. The ABS lights suddenly came on again and she said the brake pressure did not feel right and there was something definitely wrong with my brakes. After it was assessed I was informed I needed a new ABS actuator assembly and an accumulator pump for the master cylinder. Total cost was estimated as $4600.

- South Pasadena, CA, USA

I was driving my 2010 Prius in a congested area and cars in front of me stopped suddenly. As I braked hard, the car seemed to lurch forward for about one second, maybe longer, and then the brakes kicked in. I noticed that the road was rough. The surface was dry. Fortunately, I had allowed ample distance from the car in front of me, and there was no collision, but it was very unsettling. In the previous month, I had three or four less intense sensations of "lurching forward, " which occurred when I stopped at a particular intersection when I had just started the car, but the road was smooth.

- Ardmore, PA, USA

I had been hearing a lot of grinding noises that just got worse. When I went to the dealer, they discovered that my brake pads had failed/frozen. They replaced my pads and machined my rotors. They could not explain why a car I had for only a little over a year had this problem. They at first blamed my driving, and then the roads (I.e. too many gravel roads). Now, at 68,300 miles those pads have now failed again. One is completely worn down and the rotor is now rusted through. No one can explain why this is happening. When I demanded an answer, they told me that a "bulletin" had gone out to the dealers only stating that due to the pads failing, they were "redesigning" them. But, they would only replace for free those that fell under the 36,000 mile warranty. I don't understand why, in less than 69,000 miles I have had to have this repair done not once, but twice. They tell me no other owner has had this problem, but I find that hard to believe. Can anyone tell me if there are other complaints of this type, and what can be done to rectify this problem.

- Howe, IN, USA

Experienced a complete brake failure while driving 2010 Prius. Dealer indicates brake booster failing and leaked nitrogen into master cylinder which should then also be replaced. Dealer insist it is one assembly and estimates replacement to be $5,166 ($1,638 for booster and $2,466 for master cylinder). Due to the complete warningless failure of brakes while in operation it would seem to a critical safety hazard due to the design flaw in the combined brake booster and master cylinder brake assembly causing a brake failure in operation.

- Katy, TX, USA

On multiple occasions, I have experienced issues with the car suddenly accelerating while I'm pressing the brakes. Specifically, this appears to occur when braking on uneven surfaces (ie construction areas, pot holes, etc.). this can obviously become a deadly situation if one is trying to stop the vehicle and with this problem run into the car/vehicle ahead. Most recently this occurred on the surface streets in low speed, in traffic. It feels like the car lurches ahead while applying the brake. I was told by the service people at Toyota that I was making this up. I can recreate it given the right surface.

- Diamond Bar, CA, USA

When braking over rough road, brakes fail.

- Hopewell, NJ, USA

Vehicle has no brakes at all, we turned the ignition on and the car start beeping, brake light its on, ABS light on and slip indicator light is on.

- Wichita , KS, USA

The following event happened twice with this vehicle. Tin both instances, the car was running and in park with no one in the vehicle. It then down the driveway with no one in it. In the second occurrence, it appears to have gone into reverse on its own and rolled into a retaining wall causing damage to the rear passenger side bumper and back panel.

- Sioux Falls, SD, USA

Problem with 2010 Prius performing uncontrolled hard braking while driving on interstate at approx 73~75 mph. This happen on two separate occasions, with the first being Feb 10, 2013. The second incident occurred late afternoon on sat. Feb 16, 2013. Both occurrences were in light traffic, whereby preventing potential severe vehicular rear end collisions that could have resulted in serious bodily injures and grave vehicular damages. Vehicle was checked by a Toyota dealer and passes all troubleshooting tests, Feb 18, 2013. Requested additional tests be done on Feb 19, 2013. Toyota dealer could not recreate the problem. No further actions were taken by the dealer.

- Frankfort, KY, USA

This is a recurring problem. Anytime I am slowing down for a red light and there is a pothole or other rough surface condition, the car lurches forward and jumps, so to speak. Given the condition of the roads in Chicago, this is a pretty regular problem. I usually have to press the brake much harder than normal while this is occurring because of crosswalks and lights. I think this is a serious safety issue; however, when asking the dealer to look into this, they indicated that it was the anti-lock braking system kicking in, and that it was a perfectly common thing to experience.

- Lansing, IL, USA

All brakes failed while I was going 69mph on I-75 South just North of the union centre boulevard exit, approaching I-275 at the butler/hamilton county line on sat. Dec. 22.. all warning lights came on and the warning "beeps". I was in heavy traffic but was in the right lane and was able to exit on the union centre exit ramp and roll to a stop. This happened the day after I had the car at performance Toyota in fairfield, oh for the 35,000 mile check/oil change (on Dec. 21).the car had to be towed to performance Toyota on Dec 22; they determined the master cylinder failed (lost its vacuum) causing total brake failure.

- Liberty Township, OH, USA

Incident #1 brake: On January 17, 2013 as I was entering the intersection about 20mph, I applied my brakes, but they went straight to the floor and warning light started blinking. I pressed brakes very hard and car almost stop, then, its brakes gave up. There is sudden slight "unintended acceleration" and I almost hit car front of me. But, I am able to manage to drove the car into the center island. Brake was totally out, and the car started drove by itself. I panicked and pressed power button to shut off the engine. Car drove about 15 feet and stopped. After this incident, I tow my car to the dealer, they told me that lost brake is due to short circuit made domino effect to multiple computers malfunction. They will replace whole computer system, but service man would not guarantee it will never happen again. Incident #2 power failed and shut down while driving at highway. On December, 2012 and January 2013. I was driving at highway and trying to merge into the center line, car stalled and prompted "key does not detect" message on the screen. I almost hit from behind by another car. While the car still has a speed about 40mph, I managed to restart the car by depressed brake and press power bottom. It is true this car lose brake and does slight "accelerate".

- Orange, CA, USA

When driving on an uneven or wet surface the brakes seem to lag for a few seconds and the car hops forward.

- Ellicott City , MD, USA

My Prius iv, purchased new in 2010, intermittently had a lunging forward problem when going over speed bumps, pot holes etc. I would have to stop it by braking quickly, so I didn't collide with a car ahead. I informed Toyota of this problem within the first year. They tested it and said they could find nothing. I mentioned this to them on various occasions when I took the car for its periodic maintenance of 5000 mile intervals. On December 26, 2012 I was stopped waiting to go left when I was rear-ended. I went to pull over to the side of the road to assess the damage. When I accelerated to get to the side of the road, the car took off crazily, at a high rate of speed for about 6-7 seconds, zigzagging uncontrollably on the 2 lane road. If there were cars coming toward me, I would have been in a head on crash. I immediately called Toyota service of scranton, pa and asked them to see and assess the car's problem. They made an appointment and concluded.said there is no problem internally, and suggested removing the after market floormat. I then proceeded to show them the same problems many customers are having with the Prius, including an article by steve wozniak, the co-founder of apple company, who had acceleration problems with his 2010 Prius. I called the main Toyota headquarters later, explaining the problem and they too said there is no malfunction, only mentioning the floor mats again.. this is not the case as the car has had acceleration problems from the beginning and to further clarify, I was able to finally stop the car... the mat was no where near the accelerator. I am afraid to drive this for others' safety, my passengers and my own safety. I take care of my cars faithfully. You can view my records. I am also fearful if I trade this car, someone else might get injured or killed. Can you please check and advise.

- Swoyersville, PA, USA

If you go over a bump while braking - the brakes fail, and you have to take your foot off the brake and re-apply in order to stop. This has occurred numerous times - and is a serious flaw on this automobile. This car is a fleet vehicle for my company and I have asked peers if this occurs on their cars - and they have confirmed the same experience with their brakes. With all the Toyota recalls - I am unclear why this has not been addressed...?

- Chicago, IL, USA