I am experiencing momentary loss of braking capability while driving over an uneven road surface, pothole or bump. This happens frequently in my car. Sometimes even on a stop sign and making a right turn into a state high way it feels like jumping off with no control of the car.

- Shrewsbury, MA, USA

Continual problem whenever we try to brake, the car will begin to accelerate. This problem has been apparent since we purchased the car and each time we mention it at the servicing, we are told the brakes are working fine.

- Tarzana, CA, USA

In May 2009 I purchased a 2009 Toyota Prius my Prius has had similar braking problems as those described as affecting the 2010 Prius models. In August 2009 I brought my Prius in to the Toyota service department because I had experienced a significant lag in braking (more than 1 second) while slowing to a stop. Since then I have experienced the same problem on several other occasions. Unlike the first time I experienced the problem, the recent occurrences have happened when I was trying to brake and hit a small pothole and when braking and hit a lane divider. Although the media reports do not indicate that this problem affects Prius models other than the new 2010 models sold prior to January 2010 I would like Toyota and the NHTSA to be aware of the fact that my 2009 Prius is having similar problems.

- Rancho Cordova, CA, USA

2009 Toyota Prius also suffers from temporary loss of braking after hitting potholes or other rough road surface. This problem has existed since the car was new. This is an ongoing problem.

- Lexington, KY, USA

The contact owns a 2009 Toyota Prius. While the contact was driving 50 mph he attempted to stop the vehicle and noticed that the brakes were taking longer than usual to stop the vehicle. The contact also noticed that the vehicle lunged forward before coming to a complete stop. The vehicle was diagnosed by the dealer who stated that the failure could not be reproduced. There were no prior warnings. The current and failure mileages were 9500.

- Columbia, MO, USA

Toyota Prius - are you guys paying attention to this?

- Benoni, 00, USA

My 2009 model Toyota Prius is having similar braking problems being reported on 2010 model Prius. Car loses braking power when driving over uneven surfaces.

- Brooklyn, NY, USA

The contact owns a 2009 Toyota Prius. The contact stated that in slippery weather, when he depressed the brake pedal, he did not notice an immediate response in the braking system. It seemed to "lag" so he would continue pressing down until it kicked in. He noticed the issue everytime it was raining or there was slippery weather. He took the vehicle to the dealership but the dealer could find nothing wrong with the vehicle. He had not called the manufacturer to-date. The vehicle had not been repaired at the time of the complaint. The current mileage was 11,248. The failure mileage was approximately 50.

- Port Washington, NY, USA

Any time the "slippery condition" light comes on (for instance, when going over a pothole or a patch of water on the road), my 2009 Prius jumps forward. I told the dealership about this in the fall and was told that the car was working properly. Now, it appears that there are others with 2010 priuses with the same problem, but mine is a 2009. I have a young daughter and I won't put her in this car anymore because it's winter now and it happens on slippery roads nearly every time I drive.

- Berkeley Springs, WV, USA

Acceleration of 2009 Prius when braking and hit a pothole.

- Ithaca, NY, USA

Brigham physician killed in car crash top internist was loved by patients, hospital's staff she was a mother, wife, doctor, and supervisor. Globe staff / April 23, 2009 email| print| single page| yahoo! buzz| sharethistext size ' + the popular medical director of a major physicians' group at brigham and women's hospital died Tuesday after she was involved in a head-on car crash near her home in needham. Police and relatives said it appeared that an internist who for the past 27 years served as medical director of brigham internal medicine associates, crossed into oncoming traffic shortly before 6 P.M. as she was driving home from work in her 2007 Toyota Prius on greendale avenue. The 60-year-old relatively small hybrid car collided with a Toyota sequoia. The woman who was driving the sport utility vehicle and her two passengers suffered injuries that were not life-threatening, police said. Their names were not released. Investigators said it does not appear that speed or alcohol played a role in the crash, but police said they are investigating whether she was using her blackberry at the time. The speed limit on the road is 40 miles per hour. They also said it does not appear that she was wearing a seat belt. The three in the sequoia were wearing seat belts.

- Cccccc, MA, USA

I have a 2009 Toyota Prius, and the brakes do not always engage. There have been several instances where I felt that the car would not stop, one time I even engaged the emergency brake to stop it from going into my garage wall. I have had it into my dealer about 4 times, and each time they haven't found any problem and that "it is just the way the car works".

- Beaverton, OR, USA

Driving car on los angeles freeway during a gentle rain. I was going slow and a car cut in front of me and when I went to brake, the car began to accelerate. Took car to hamer Toyota in mission hills and they tested the car and said the brakes were fine. Today's headlines that I am not the only person that is experiencing this problem makes me all the more concerned.

- Tarzana, CA, USA

While crossing a small bridge over an expressway, applying brakes at the point of bumpy transition caused the vehicle to lurch forward for approximately one second. This caused a sudden panic, but no other effects. This is the second occurrence at the exact same bridge transition and bump over the course of 8 months. There are no recognizable side effects. This has not been reported to the dealer, nor to the company.

- Santa Clara, CA, USA

On Dec 11, 2009, I was driving down a street in cambridge, MA (I had a coworker in the car) and we were in stop and go traffic at a stop light. The car in front of me crawled up to approach the light after several cars had gone through-then stopped @ the red light. I proceeded to do the same. When I applied my brakes to stop there was no response, so I pressed down harder-still no response. I then began to pump my brakes to avoid the accident but there was still no response from the braking system. If the braking system had not failed I would have more than enough response time and distance to stop but my car kept @ a steady speed and ended up rear ending the car in front of me. No one was injured but there was minor damage to the car in front of me and $1800 damage to my car. I've had other instance where I've hit potholes in the past while slowing down- and the brake system would stop momentarily from working. I work in the boston area- where I'm constantly in stop and go traffic. I've experienced 2 previous times slight brake delay-which I've compensated for and give myself more room between my car and the car in front of me. In addition there was one instance 4months ago where I was coming to a stop- and I heard one of the motors (I'm assuming the electric B/C it charges as you stop) rev up and my car jilted forward- as if I had stepped on the gas but I had my foot on the brake the whole time. That was the only instance of that. I've had my car since April 2009 and when the two instances of brake delay occurred, I had the Toyota service center check my brakes and they came back stating they were fine. After the accident I did report the failure to Toyota and have yet to hear from them about it. I would like to note that there are several sites online with customers complaining about brake failing/delaying at speeds less than 20mph.

- Worcester, MA, USA

I am writing to let you know of a problem I am experiencing with a 2009 Toyota Prius that I purchased new just one week ago and which still has less than 500 miles on it. A couple of days ago I was approaching a stop at an intersection, in town where my speed had been only about 15 mph. While my foot was on the brake, just prior to a full stop, the car accelerated on its own. I kept my foot on the brake, pressing hard, and the brake eventually overrode the accelerator and stopped. Looking at the dash I saw that the ABS brake light flashed on briefly. It was a sunny day, no rain, no slick surface. No one was in front of me, so no damage to me or anyone else. Another incident happened this morning in my garage. I got into the Prius, foot on the brake, pushed the power button, and then a moment later, still in park, I felt a surge. The car did not lunge forward, but I strongly felt the revving and surge of power, and the car lifted from the power. These incidents caused me to search the web for similar experience of others, and I have found many, some with severe consequences. I would also like to add that in hindsight I realize that two other things I have noticed about the brakes might be important to relate. I sometimes hear a slight grinding disk sound when I brake, and I have on a few occasions noticed that the brakes are skipping and the ABS engaging, as if I were on a slippery or graveled surface. Yet that was never the case; the road conditions were dry and tar was in good condition. I know this because I looked back each time to see what might have caused the brakes to act strangely. There was no apparent cause. In retrospect, after having experienced the acceleration at the stop sign, I realize that these other odd braking issues might be symptoms of the bigger braking issue.

- Arrowsic, ME, USA

The contact owns a 2009 Toyota Prius. While driving 5 mph into a parking space, the brakes did not work when the pedal was depressed. On two separate occasions, the vehicle struck a garage door and the contact rear-ended another vehicle due to the brake failure. There were no injuries. The dealer has not been notified. Currently, the vehicle is in the repair shop for the body damage, not for the brakes. A police report was filed. The failure and current mileages were 1,200.

- Sedona, AZ, USA

The contact owns a 2009 Toyota Prius. While driving approximately 25 mph on a lightly snow covered road surface, the brakes did not respond when the pedal was depressed. The vehicle failed to slow down. There were no warning indicators illuminated on the instrument panel. The contact crashed onto the curb in order to stop the vehicle. The driver was uninjured, but the vehicle sustained severe damage. The vehicle was towed to an authorized dealer for inspection, but they could not determine the cause of the failure. The vehicle is in the process of being repaired. The failure and current mileages were 480. Four days after purchasing the vehicle, the consumers was heading down a gentle incline toward a traffic light at an intersection shortly after a light snowfall, the street was wet, but there was no ice on the road. As she braked to slow down, she noticed there was no deceleration and continued to press down on the brake pedal to no avail. To avoid crashing into other cars, she veered sharply to the right into a curb and came to a stop. The vehicle sustained extensive damage to the wheel, axle and undercarriage. The vehicle was towed to the dealer and after the inspection, the consumer was informed there was nothing wrong with the vehicle. The dealer implied the she must have applied the brakes incorrectly and was not accustomed to ABS. A few months later on another wet rainy day, there was a similar incident of brake failure. Updated 04/15/10.

- Larchmont, NY, USA