Braking momentarily fails after hitting a bump, pothole, or other road irregularity. This article describes the issue perfectly. www.thedetroitbureau.com/2009/12/NHTSA-tracking-braking-loss-on-Prius-hybrids/#more-17003 dealers since day of purchase have said there was "nothing wrong".

- Ewing, NJ, USA

I have made complaints to the dealership since I purchased my 2005 Toyota Prius regarding a momentary brake failure when driving over a bump or hitting a pothole. I have been told everything from "it is just how ABS works" to "you need to hit the brake harder when you come to a stop" (I.e. rather than a slow and careful stop, a quick and sharp stop). There are too many incidents to name but one that occurs routinely is about 30 yards away from a stop sign leading into the parking lot at my place employment. I now have to coast very carefully and prepare myself for brake failure. Should there be cars around, this becomes a dangerous matter. Again, this happens routinely and none of my complaints have been taken seriously by the dealership.

- Sylvania, OH, USA

The contact owns a 2005 Toyota Prius. The contact stated while driving at unknown speeds, the brakes would not engage when depressed. The dealer was unable to duplicate the failure. The contact stated the failure would occur intermittently for years. The vehicle had not been repaired. The failure mileage was 427 and the current mileage was 50,000.

- Alexandria, VA, USA

48 mph traveling North on or 217; without cause and simultaneously brake warning light on ABS warning light on vsc warning light on audible alarm steady tone then try to stop: Brake pedal up high, brake pedal unresponsive and hard to press, immediately pulled of on allen exit; brakes still unresponsive, pressed maximum force on brake pedal brakes locked up the wheels skidding and burning rubber.

- Portland, OR, USA

2005 Toyota Prius--experiences braking and handling failures when braking on uneven or wet surfaces. When we are braking and hit a pothole, gravel, railroad tracks or wet surfaces, the car feels as if we are losing control of it, and braking seems to temporarily stop. The "skid danger" light comes on, even at very low speeds. This happens nearly every time we brake under these conditions. Also, at idle (ie. Stoplights), the car will frequently lurch forward slightly, even with the brake pedal fully depressed, especially when engine transfers from electric to gas. We were told early in our ownership that this is normal "dieseling". these have been on-going problems, since we purchased the car in 2005 (new), that we thought we were "imagining" until hearing all of the reports of similar problems.Toyota claims that the Prius braking issues only affect the 2010 Prius, but we see it firsthand on an on-going basis.

- Watkinsville, GA, USA

2005 Toyota Prius brake failure the consumer stated she drove into a parking lot, made a sharp left turn, and then a sharp right turn into a parking space and experienced complete brake failure. The only thing that stopped her was an elevated median between parking rows and the fact that she was going very slowly. After several days of the vehicle being at the dealer, they were unable to find a problem. The consumer has since traded the vehicle, because she did not feel comfortable driving the vehicle any longer.

- Sarasota, FL, USA

About 6 months ago, I was on I-95 in ft. Lauderdale, just exiting: I touched the brakes to slow -- and they firmly locked. I touched them again and, fortunately they worked normally. Had this happened while I was still on I-95, there would have been a horrible accident. I reported this to Toyota, at their nyc headquarters, when their other problems became public. This has not happened again, however, I no longer take any passengers, and I drive much more cautiously!

- Delray Beach, FL, USA

The contact owns a 2005 Toyota Prius. While driving at speeds of 45 mph, the ABS warning light and master warning light indicator illuminated on the warning panel. The driver experienced total brake failure. The vehicle was towed to the dealer for possible repairs. The dealer replaced the battery in an attempt to correct the failure. The vehicle exhibited the same issue again after the repairs were performed. The current mileage is 71,000 and the failure mileage was 67,079. Updated 05/11/10. Updated 06/03/10 updated 06/04/10.

- Port Matilda, PA, USA

I have been routinely bringing my 2005 Prius to a Toyota dealership every 5K miles according to manufacturers suggested maintenance schedule and never had a problem reported to me. (one time the software needed to be reloaded.) on the evening of the incident that I am reporting, I had traveled on the mass turnpike and rte 495 (~38 mi) home from work (~9:30 pm) and successfully slowed and stopped my 2005 Toyota Prius as needed. As I got into on local roads, I suddenly lost my braking ability. Fortunately I was going slowly and was able to roll to a stop. There was a really shrill alarm and a red light showing ABS (antilock brake problem)--I'll say. I tested to see if there was any braking power so that I could get the car home. If you pressed the brake to the floor--there was some residual slowing--so I crept home. Aaa towed my car to Toyota the next day and Toyota ultimately identified the problem as a computer problem. They replaced the 1 89540-47130 computer assembly, skid. Aside from the cost ($2250), its the possibility that I could have lost my brakes on either of the two highways that I take on the way home, exit ramps, toll booths, and that I or some others could have been seriously hurt, really upsets me. And how do I know that this will not fail again? regular service does not check computer status. I think that you should look into computer problems with Toyota and also what Toyota includes in regular service. They say that they haven't seen this before, and that may be true: I have a 5 yr old Prius with more than 110K miles on it and I'll bet that is a lot of mileage for a Prius. As more people drive Prius's for longer times and accrue higher mileage, I would bet that Toyota will see a lot more of these incidents. I think that you should be proactive and deal with this before people get hurt.

- Milford , MA, USA

Although I have never had an accident because of it, my Prius (2005) has a habit of lurching forward when I hit the brake the stop at a light, for example. Rather than decelerating the car suddenly speeds up before coming to a stop. This happens about once a week. Sometimes it does not happen for a couple of weeks and other times it happens a couple of days in a row.

- Hartford, CT, USA

I was traveling down a residential street and approaching a pedestrian intersection when a pedestrian on her morning exercise run suddenly ran across my path. I immediately tried to stop, but the edge of the sole of my dress shoes were caught behind the brake pedal, and I was unable to move my foot onto the pedal to depress it. Only by steering away from the pedestrian, and her action to stop, did I avoid a serious accident. The cause of this incident is the fact that the accelerator and brake pedals are displaced by several inches, that is, the brake pedal is closer to the driver than what the accelerator is. This requires one to lift your foot by 6 inches or so before moving it over to the brake pedal to depress it. In an emergency situation your reflexive reaction is to try to move your foot over as quickly as possible. However, the displacement of the brake pedal creates an obstacle than, in the best case, results in a delay, and in the worst case results in an inability to operate the brake pedal in time to avoid an accident.

- Eagan, MN, USA

Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6) 2005 Toyota Prius [xxx] when braking on uneven/bumpy road (even freeway lane divider bumps), skid light come on and braking force is reduced. Has happened at both low and high speeds. No issue on smooth roads. Has occured several times, over several years, have never had the brakes serviced. Last occured 3/3/2010.

- Thousand Oaks, CA, USA

ABS braking system on my 2005 Toyota Prius will lock the drive wheels leaving you stalled in the middle of the road/turn. The accelerator can be all the way to the floor - engine racing - I have had to sit for 30-45 seconds before system released the drive wheels.

- Madison, WI, USA

I would like to file an official report of my accident that involved my 2005 Toyota Prius on January 13 of this year. It was in the morning after I had dropped off my children to their school. I was driving down the hill and driving the normal 25- 30mph down the hill to go home. Upon coming to the stoplight, I noticed the cars in front of me stopped at the stoplight so I went to hit my brakes and did not feel any power from my brakes so I quickly stood on my brakes with both feet and realized I had absolutely no brake power. I subsequently crashed quite hard into the car in front of me and experienced severe pain to the right side of my neck. After initial shock, I was able to maneuver my car out of traffic to a parking lot and noticed it funny that my brakes were working at that point. After exchanging information with the man that I hit, my car was towed to an autobody shop. After going to kaiser to look into my injury (which was whiplash) I was told at the autobody shop that my car was totaled and could not be fixed. He also told me that my airbag did not deploy because I had hit a larger american car which was higher than my bumper. It never hit the airbag sensor on my car that was lower than the impact point. After the accident, I asked my insurance company, the interinsurance exchange of the automobile, to please look into the brake situation and they stated that they did not find anything wrong. I am not satisfied with this answer because I have read that the Toyota problems are not easy to diagnose. I have been driving for 27 years and have never been in an auto crash that was my fault. I also have never experienced such a scary feeling as having absolutely no control over my car.

- Redondo Beach, CA, USA

ABS service light and brake light came on. When braking vehicle bucks - driver hesitated to drive car few miles to dealership. "ABS code C1247 strolesensor malfunction performed linear int and calibrate. If condition recurs ABS ECU may be faulty" - (9/7/06) "ABS light comes on. Code #C1247...internal open circuit in skid control computer, replaced computer. - (3/20/07) ABS light on. Diagnosed brake pedal stroke sensor internally shorted code #C1247. Replaced sensor. (4/23/07). The preceding was taken from the dealership service department's notes on their service sheets. After the three trips to the dealer the problem appears to have been solved -- obviously an electronic part that might have had serious consequences depending on the circumstances.

- Riviera Beach, FL, USA

The contact owns a 2005 Toyota Prius. The contact stated that when the traction control engaged, the brakes would release for a second. He noticed the issue on a bumpy road and he saw the traction control engage when the light on the dashboard illuminated. The problem occurred whenever he had to brake on a bumpy surface (1-2 times a month). He had not taken the vehicle to the dealership or called the manufacturer to-date. The vehicle had not been repaired at the time of the complaint. The current mileage was approximately 98,100. The failure mileage was approximately 2500.

- Kent Lakes, NY, USA

2005 Prius brakes fail temporary when traveling over bumpy surface. It occurs weekly. No consequences yet. Nothing done to correct the problem.

- Tallahassee, FL, USA

Please note this is my second complaint about my Prius's brakes, but it is not a duplicate complaint. My car has two problems with it's brakes which seem to me to be unrelated. My Prius brakes very oddly when driving in the rain, or in the early morning when there is appreciable dew/condensation. When gently depressing the brake pedal at a constant pressure, the car decelerates slowly, then abruptly transitions to very rapid deceleration, as though I had slammed the brake pedal down hard. It is very difficult to modulate the braking. This happens several times, then seems to ease up as the vehicle is operated for around 15 minutes. On several occasions I have reported this to the Toyota dealership. They have sometimes dismissed the complaint out of hand, and once attempted in vain to replicate the defect, unsuccessfully. In any event, I have always been told my brakes were operating normally. Please note that this is not the same problem as the brake failure which occurs when braking while riding over a rough or uneven surface, which my vehicle also does. At least, I assume the two problems are unrelated. I have filed a separate complaint form for that problem.

- Brooklyn, NY, USA

On 11/5/09 in mid-afternoon I was driving my 2005 Prius North on calvert St. In baltimore city, just above saratoga St., at about 25 mph when the traffic in front of me slowed. At the time I was speaking to my boss on my verizon cell phone using my bluetooth headset. I applied my brakes and the car was braking as usual slowing down normally until about 10 mph, or so, at which point I felt the car bounce very slightly and gently as if there was a small gradual dip and rise in the roadway surface. My foot was still applying light pressure on the brake pedal as I intended to come to a near crawl as I neared the car in front of me, but after the slight bump the brake pedal gradually went to the floor and my car proceeded without any braking in effect. After the pedal was depressed to a point near the floor I pumped the brake pedal once and press on it as hard as possible. At this point the right rear wheel brake applied and the rr tire squealed as it appears it was the only one braking. I continued pressing until the car came to a stop at which point I notice that several of the instrument panel lights were now on, including the ones for the brake, the ABS, and vsc. I then continued driving slowly home, about 2 mi., because it appeared that only the rr brake was working and that there was not power assist with the braking. When I got home I turned the car off and then back on to see if the problem persisted, and upon restart the brakes appeared to work properly and some or perhaps all of the warning lights were off. I took the car to bill kidd Toyota in timonium, md on 11/9/09 and they reported that scan code C1357 was present. They reportedly contacted Toyota tech assistance who instructed them to clear the scan codes and perform linear solenoid calibration. They road tested the car and said it was ok to drive. My boss was on the phone with me during the entire incident and hear the rr tire squealing and we discuss what was going on. I am a mechanical engineer.

- Baltimore, MD, USA

The brakes began to noticeably grab then release at low speeds, but it was intermittent. My son was driving, slowed for a stop light and hit the car in front of him when the brakes released. I took the car to the dealer, they could not recreate the problem and told me no fault was detected. Three weeks later, driving back from Washington, through Oregon, we pulled into a gas station, the car slowed at first, then the breaks let go and my husband had the stomp on the pedal. He turned off the car, filled it with gas, and when he turned it back on all the warning lights went off, signaling brake failure. We had it towed to a dealer in roseburg, and the brake sensor had faulted. But they told us we could probably drive back to sacramento. We decided to have it replaced there and not risk driving it any further.

- Sacramento, CA, USA