Problems with 2010 Toyota Prius SERVICE BRAKES, HYDRAULIC

I live in the phoenix, az area. while driving my 2010 prius, when i go over an abrupt bump with brakes engaged braking completely fails momentarily. first few times this happened i thought maybe my foot had reduced pressure on the petal due to the bump but later confirmed that this is not the case. it occurs almost daily - every time i go over an abrupt bump with brakes engaged. i have a daily drive that takes me over some slightly rough pavement as i approach a stop light. nothing has been done to correct the problem - i am just aware of it and am careful to account for that occurrence as i approach the light. *tr

I have noted a braking issue with my 2010 toyota prius v equipped with a navigation system. the brakes do stop the car, but seem to delay stopping the car after the applying the brake. the car was purchased in august 2009. i have not been contacted by toyota. *tr

1.i purchased this 2010 prius in august 2010. i have experienced unanticipated acceleration two times since the last (initial) service. once with my husband driving on route 17 and the other time while i was driving on a local road. 2.as i stated in my service paperwork when the car was first serviced, there is a problem with the brakes. they do not stop on uneven road surfaces, such as pot holes, bumps, etc. your service department said that this is caused by the abs and it is ?normal?. obviously there is still a problem. please advise what will be done to correct this issue. 3.when start the engine first thing in the morning (or when the car has not been driven for a while) often, but not always, it makes a grinding noise when starting *tw

My 2010 prius hybrid has a problem in certain instances when i apply the brakes. the first time it occurred was when i was applying the brakes to stop in front of my home. there were wet leaves in the street and when i applied the brakes, there was a moment when nothing happened. then it felt as if the abs system actuated and momentarily the brakes locked up and the car started to skid, then the abs took over and the car came to a stop. truthfully i was frightened. i have owned the vehicle since september, 2009 and this has occurred several times. i was lucky one time when it happened in traffic when the vehicle in front of me stopped suddenly. i was sure i was going to hit the other vehicle but it moved forward far enough so that i did not hit it. i have noticed that it occurs most often when the street or highway is rough or bumpy in the area where i am braking. it is especially treacherous here in minneapolis when the streets are slick from snow or ice. i certainly have learned to give the other car plenty of room so that i will have time to brake. however there are occurrences, such as 4-way stop signs, where it is almost impossible to allow enough space. *tr

Our 2010 prius unexpectedly lurches when braking. this occurs when it hits a pot hole or when the surface is slick / slippery. it does it every time a certain pothole is hit - that is, we can reproduce the lurching. this lurching, which feels like an unexpected acceleration, significantly and unexpectedly increases the stopping distance. this has almost resulted in the prius striking the car in front of it. it makes it impossible to safely judge your braking distance in order to come to a safe stop because you never know when this phenomenon will occur. this also puts pedestrians in the cross walk at risk, since the ability to stop accurately is affected. we have taken the car to the dealer twice. they are able to reproduce the phenomena. however, they say that the car tests out "within specifications", that there is nothing wrong with the vehicle, that it is just the way it is made, and that we just have to get used to it. they say there is nothing to fix or repair. they took another 2010 prius off of their lot and ran it over the same pot hole and it had the same problem. an article by paul a. eisenstein, msnbc.com contributor, updated 7:29 a.m. et, tues., dec. 29, 2009 describes exactly the problem we are having, and it seems to be related to the braking system. this does not seem to be a problem with only my vehicle - it appears to be a fleet-wide problem. having the brakes cut out unexpectedly is a major safety concern. we do not feel safe driving the vehicle. *tr

2010 toyota prius brake issue. we are experiencing a momentary loss of braking capability while traveling over an uneven road surface, pothole or bump. *tr

I have a 2010 toyota prius and have experienced the braking problem. when braking with the foot off of the gas pedal, the car will lunge forward with acceleration. it will stop when i hit the brakes harder. this is happening on dry pavement. this has happened on 3 seperate occassions. *cn

I own a 2010 toyota prius. while braking on a slick or rough patch of road my car will briefly surge and then brake. at first i thought this happened because the car has low friction tires for efficiency. it has happened about 5 times since i bought my car in august 2009. after reading the recent reports it seems like i am having a braking problem, not a tire problem. *tr

I purchased a 2010 toyota prius on 8/26/09. the car would accelerate when i stepped on the brake to slow the car down at a stop sign or red light. i brought the car to plaza toyota on 12/23/09 after this occurred more than 50 times. toyota told me that there was nothing wrong with my car and i'm the 1st one to complain about this problem. on the receipt (r/o # 6311675/1) from this visit, toyota stated," tom the toyota field tech determined that the feeling that the customer is experiencing is normal and that the regenetive braking system and hydraulic system is transferring and that's normal." since that visit, this problem has only happened 4 times. in regards to braking on slippery roads, the car has slid 2 different times before gripping the road. also, toyota claims that the prius gets 51 mpg, this car has only been averaging 33 mpg in city driving. *tr

I own a 2010 prius. the day after the purchase, the brakes would grab when in reverse as brakes were applied. i returned to the dealer who said they could find nothing wrong and was perhars due to a little rust on the rotors and and to return in problem recurred. the grabbing and jerking continued while braking in reverse at low speed and i again returned to dealer. this time they said it could be due to interaction between the mechanical brake and the the regenerative brake but had no improvements to offer. the problem continus to date. it does not happen when going forward . however, i thought you might be interested as it may indicate a general software error ifor controlling the interaction between braking modes. *cn

When applying brakes on my prius 2010 while approaching a stop sign or light, if i hit a bump, the brakes will briefly disengage. this has happened on numerous occasions since i purchased the vehicle last summer. *tr

We took this statement from the nhtsa press release with today's date, which is a 100% accurate description of our problem: "momentary loss of braking capability while traveling over an uneven road surface, pothole or bump" this is not a one-time event as we've noticed it happening numerous times since purchasing the prius in august 2009. the hesitation we've experienced usually occurs when driving down a steep hill or passing over a pothole. *tr

Tl*the contact owns a 2010 toyota prius. the contact stated that the brakes were ultra-sensitive and while driving 5 mph in reverse and lightly depressed the pedal the vehicle lunged forward as if she made an abrupt stop. occasionally, she had to push the brake pedal extremely hard to stop the vehicle. she has not spoken to the dealer nor the manufacturer to-date. the vehicle had not been repaired at the time of the complaint. the current mileage was 3,740. the failure mileage was approximately 500.

Tl*the contact owns a 2010 toyota prius. while driving 10 mph over railroad tracks engaging the brake pedal the vehicle failed to stop and accelerated. the failure occurred intermittently; therefore, when she took the vehicle to the dealer for routine maintenance, she did not mention the failure. she will take the vehicle back to the dealer to be diagnosed. the failure mileage was 4 and the current mileage was 5,600. updated 08/12/10

I have a 2010 toyota prius. when i am braking and i happen to hit a bump in the road, my car lurches forward while my foot is on the brake. i have not had an accident, but it has been close a couple of time. this began happening almost immediately after i bought the car. i bought it in july 2009. incidents occurred between august 2009 and continue through the present. p.s. i don't know what type of brakes they are: air, hydraulic or electric - i just picked one. *tr

My prius loses its braking ability when i hit a pothole or if i drive over a sewer grate. i've owned the car since july 2009, it is a 2010 model. it also happens when i drive over bumps in the road. this has happened several times since july. it seems to happen more in wet weather. *tr

The brakes were a problem in my prius 2010 from beginning. it would accelerate on braking. happened 3 times. i had no floor mats at that time in my car. i took it for my 1st oil change to koons toyota, annapolis in oct last yr and complained about it. at that time, i had put mats. they blamed it on mats. they test drove and said its fine. told me to bring it back if problem persists. i kept driving and this last month's snow made it all apprant again. would not brake but accelerate on snow, happened 4 times on one trip. i am not driving it anymore on snow days. relying on honda odyessy- much more stable. its surprising, toyota prius 2010 was last to be recalled with so many complaints on board. *tr

Tl*the contact owns a 2010 toyota prius. while driving 15 mph with the brake pedal engaged it failed to respond which forced her to apply pressure to the brake pedal in order to stop the vehicle. the vehicle also lunged forward when the contact drove over a pothole. the dealer stated that since the vehicle was brand new it was adjusting to her driving pattern. the failure has occurred approximately 6 times. no repairs were made to the vehicle. the failure mileage was 1000. the current mileage was 6292.

Tl*the contact owns a 2010 toyota prius. the contact noticed that there were occasions when he lost braking power and slight acceleration when he drove over a pothole or bump in the road. he stated that the issue occurred when driving at low speeds in normal road conditions. the contact was able to regain control and resume normal operation almost immediately after the failure. he experienced the issue at least 12 different times. he had neither taken the vehicle to the dealership nor spoken with the manufacturer at the time of the complaint. the vehicle had not been repaired to-date. the current mileage was approximately 3,000. the failure mileage was approximately 150.

2010 toyota prius brake failure. everytime while braking if there is a bump or on even a slight bit of ice on 1 wheel only, the brakes will release completely and go back to accelerating rather than braking. it happens when i exit the highway and there is a change in surfaces from tar to concrete. it happens very often and can happen anytime. this occurs at any speed from 10mph up and i have experienced it from 10mph and as high as 55mph. the problem first occurred around 500 miles on the car and i now have over 8500 miles. this started in august around the 15th. i have a 2007 hummer h3 and i have compared the braking with the same conditions and speeds and the prius is not responding correctly. the hummer brakes even with the changes. i have also compared on a 2006 volvo s60. these brakes are failing and it will eventually result in a crash or a pedestrian being struck. there is no pulsing of the breaks there is only releasing for ice or for any surface other than perfect. there should be some type of repair or recall immediately. i have noticed this but thought it was only me until i saw the msnbc article. i will not let my wife drive this car since she is pregnant. it is not safe. while sitting at traffic lights the traction control light keeps turning on and blinking and will lock the brakes until the gas pedal is pressed. i have never had an anti-lock or any type of breaking issue in 15 years of driving various vehicles. *tr

Tl* the contact owns a 2010 toyota prius. the consumer stated the problem has occurred a total of 4 to 5 times. the dealer was contacted and they stated that they never heard of this problem and if it occurred again to give toyota a call. there have been no repairs done to the vehicle. the failure mileage was 2000 and current mileage was 8200. updated 3/17/10 *cn the consumer stated when he approached a stop light at the top of the ext ramp, at less than 35 mph, he encountered a bumpy surface in the road and the brakes seemed to suddenly release and the vehicle rolled ahead. the brakes seemed to re-engage moments later, preventing the vehicle from hitting in car ahead. it was a moderate stop on dry pavement with consistent pressure on the brake pedal. updated 05/20/10

I have a 2010 prius that is now about six months old. i thought i was nuts when i described to my wife the incident of braking over a manhole cover and feeling the car seem to slip and jerk forward for a second. seeing an article at cnn.com this morning caused me to write as this appears to be an issue. *tr

Tl* the contact owns a 2010 toyota prius. while driving over large and small speed bumps the vehicle accelerated without warning. as a consequence his risk for serious injury and crash were increased. he is in the process of having the vehicle inspected to determine the cause of the failure. the failure and current mileages were 1,000. updated 09/14/09 *bf the consumer stated on 6 separate occasions , with 2 different drivers, sudden, brief and unexplained engine acceleration was experienced when a bump was hit in the road while applying the brakes. the driver could hear the engine rev up and there was a surge of power from the engine despite his foot not being on the accelerator, but being on the brake. in each of the 6 incidents the consumer and second driver were able to stop safely, bit were put at risk of an accident and/or injury due to the erroneous acceleration. updated 09.15.09. *jb updated 10/13/09. *lj the consumer stated the cruise control was not engaged and it didn't feel like the anti-lock brakes engaged either. updated 10/13/09 the consumer also experienced braking problems as well. the consumer stated the problem has greatly diminished. updated 02/05/10.

My 2010 prius has had 4 instances when brakes didn't work. all involved slightly wet surfaces on a sem- potholed road in houston tx. i am taking car into fred haas toyota ,, but i am not sure anyone knows how to fix it yet. after trying to brake, there is a lurch forward before it comes to a stop. i do not feel safe in vehicle. fortunately, i was going less than 40 mph when it happened, and have not had an accident. *tr

2010 prius - confirming reports about brake failure. at the company i work, there are rumble strips leading to a gate when departing the grounds. i have learned to slow way down before hitting the rumble strips because i almost hit the bar that rises at the gate the first few times after purchasing the car last summer (2009). the brakes briefly fail then kick in again. have not been on rough terrain but i'm sure this would occur similar to the rumble strips. *tr

Pressing brakes while turning and hitting a pothole causes car to surge forward. *tr

Loss of braking capability on rough surface or bumps. *tr

I purchased my 2010 prius on august 4th, 2009 and almost immediately noticed issues with the brakes. i distinctly remember driving in the car on this date with my wife as we were on our way back from her ultrasound. i just got off the highway and there was a red light ahead with several cars stopped at it. i applied the brakes slowly and steadily, as i normally do, braking with plenty of time to stop. as i approached the last car at the stop light i encountered a pot hole and the brakes disengaged. i could feel the car was no longer decelerating. i had to slam on the brakes and barely avoided slamming in to the car ahead of me, stopping with literally an inch between our bumpers. since that date i have encountered this exact same scenario several times a month and have come close to an accident 2 to 3 times. *tr

I have experienced two problems with my 2010 prius v that i purchased last summer. first, on approximately 6-8 occasions, my car has not stopped immediately when i applied the brakes. this occurred 3-4 times when i approached a stop sign on a road between my home and church. the surface of the road approaching the stop sign had been scraped and roughened to get ready for re-paving. as i approached and applied the brakes, my car surged forward for about a second, but i was able to stop. this happened 3-4 times in other locations, as well. it is an incredibly strange and helpless sensation. this problem was probably noted between late august 2009 and last occurred about three weeks ago. even though i was forced to put an exact date in the field below, i have no idea now when the exact dates were in which this braking issue occurred. when i brought my car to the dealer for its first oil change, i described what had happened but was told this had nothing to do with the other problems that had been identified in the media as to other cars. the person at the service desk just kind of ignored my comments and was not interested in hearing about the braking issue further. the second problem i have experienced is that when using the cruise control accelerate function the car just continued accelerating even though i was no longer turning the cruise function lever. this stopped when i applied my brakes. it did cause me to stop using the cruise control during that trip though. the cruise control issue probably occurred last august in i-5. *tr

Braking problem noted with prius 2010. on uneven pavement while strongly braking, the car lurches forward for a moment, prior to finally braking (felt as though it was "slipping" until it caught the pavement again). this has occurred approximately 5 - 6 times since purchase 07/31/09. contacted service dept. in 2009 by phone, but they had no other complaints. at some level i was thinking it was just my imagination or some kind of high tech glitch that i had to live with. at servicing in january all systems were assessed without abnormality, although i did not formally complain about my brakes at that time. the issue remains, and i do believe that it is a safety issue, and that rear-ending another vehicle is a real possibility due to lack of control. *tr

Tl*the contact owns a 2010 toyota prius. while driving 30 mph the vehicle became difficult to stop when he drove over speed bumps. the contact stated that when the vehicle surged forward it felt as if he lost braking ability. the contact has not taken the vehicle to the dealer to have the failure diagnosed. the failure has occurred since the vehicle was purchased. the contact is concerned that a crash could occur if the vehicle continues to lunge forward. the failure mileage was 4,500.

We own a 2010 toyota prius which we purchased in june of 2009. on six different occasions we have experienced braking problems. one incident was on ice and when the brake pedal was pressed the response was as if there were no brakes at all and the vehicle slid freely for a brief moment. the other five incidents involved braking on a rough surface when approaching a stop sign (3 different locations). in these cases, when the brake was pressed the car did not begin to stop immediately. in fact i got the feeling that the car had been "hit from the rear" and i jerked back into my seat a little and felt that the car floated ahead before it began to stop. this all happened very quickly. i tried to replicate the situation and was successful once. in all but one of my experiences with this dilemma, the road was on a slight downward slope approaching the stop signs. there seems to be a certain speed that is needed for it to happen. toyota examined the brakes and said they were ok. obviously, they are not. *tr

This is in reference to my 2010 toyota prius which has on several occasions exhibited the momentary loss of braking when the pedal is depressed and i hit a bump. this has occurred three separate times since july of 2009 when i purchased a new prius from sunrise toyota in oakdale ny. *tr

I bought a 2010 toyota prius in august 2009. in addition to the braking problem i describe below, i also have an acceleration problem. i questioned my toyota dealership about the fact that when i am braking over metal (manhole cover, repair lids, etc.) the car is quickly pushed forward about 3 to 4 feet. several other new owners said they had the same experience. the dealer said that when they checked with toyota, they were told that the hybrid battery motor used a magnet and the braking system to recharge it. and that the push forward was from the repelling action of the magnet. my sisters own a 2008 camry hybrid and 2008 prius, and they both have experienced this propelling motion when on metal surfaces also. the problem with the dealers advice to "not brake on metal surfaces" doesn't help in snow or water situations. will this problem be fixed by the abs brakes software change?? i also had several instances where the brake pedal would suddenly go to the floor and produce very little braking power. the problem was intermittent and the dealer said they found nothing wrong. since then i have had several other instances where the brakes didn't work well and i almost hit the car in front of me. so i now drive with a lot of distance between me and other cars because i don't know when it will happen. i should say that i've had other cars with abs brakes and this car does not feel like i have them. on slippery surfaces (snow, water) the brakes do not pump themselves like other abs cars that i have driven. i have dropped it into low gear to help brake. these things have happened many times since i bought the car. i have been very careful and not had an accident yet. *tr

Tl*the contact owns a 2010 toyota prius. while driving approximately 15 mph over a speed bump or pothole the vehicle accelerated for a few seconds while her foot was on the brake pedal. although the surge lasts for a few seconds and occurred consistently she doesn't have control of the vehicle. the vehicle was taken to the dealer who stated that the accelerator pedal was operating normally. the failure mileage was 8,000.

I own a 2010 prius purchased in july 2009. i have also (regularly) felt a surge forward when braking and hitting a bump or pothole. based on my readings of chat boards i thought this was normal, although it is quite alarming when it happens. i'm not confident that my local toyota dealer would be entirely honest; when i was in for service during the floormat brake recall i overheard a service manager telling a customer it was nothing to worry about; it was only when people put non-manufacturer's floormats on top of the toyota ones that there was a problem (which is not my understanding). i'd like to be kept informed of the status of the investigation if at all possible. i'll put in early august as the "incident date" but it happens regularly (at least once a week?) *tr

Tl* the contact owns a 2010 toyota prius. the contact stated when depressing the brakes to stop the vehicle it is grabbing and jerking. while using the vehicle's speed control upon setting it the vehicle would accelerate, but when the brakes are applied the vehcile would operate normally. the contact stated that he monitors the failures. the vehicle has not yet been diagnosed by the dealer.the failure mileage 6,200.

Brakes sporadically grab and make smooth braking impossible. these are unexpected and intermittent. it occurs maybe ten percent of my trips. consequences are jolting stop. nothing allegedly can be done to correct the failures. *tr

2010 toyota prius. consumer states rear brakes released or slipped and vehicle sped up. *tgw the consumer stated within the first month of driving, she drove over an uneven, perhaps potholed area in the road and it seemed as if the vehicle's rear brakes released or slipped, and the vehicle sped up. the vehicle then seemed to correct itself and drove smoothly ahead with proper braking. *jb

I have experienced very strong grabbing sensations from the brakes a few times when backing up. the car reacts as though you are slamming the brakes even though only slight pressure is applied. *tr

Prius 2010, purchased july, 2009, dch toyota, mamaroceck, ny. braking problems since purchase: brakes disengage, car jumps, steering wheel needs to be controlled - while going over a bump, pothole or ice. in order to accommodate to this defect i must drive car carefully and slowly. this occurs regularly on routine drives in the metropolitan area. *tr

When driving, and going over a rough spot in the road (pot hole, crack, etc.) the car feels like it is lurching forward momentarily, as if the brakes released. this happens every time the car goes over a rough patch in the road. *tr

I purchased a 2010 prius in july 2009. whenever i go over a bumpy road or hit a pothole while braking the car will lurch forward. i brought it to walser toyota in bloomington, mn for this problem. they said my brakes work fine. i'm still having the problem. in fact...i have it so often we have nicknamed it "prius braking." so each time it happens we say "prius braking." we know to not follow closely to anyone at a stop sign or stop light in fear of rear-ending them when the "prius braking" happens. *tr

This is not the same 2010 prius brake problem being reported regarding transient brake failure. while waiting in gear at a traffic signal with foot on the brake pedal, the pedal slowly sinks all the way to the mechanical stop. however, the car does remain stopped even when the accelerator pedal is briefly tapped. the behavior is repeatable and consistent. personally verified that there are no external hydraulic leaks. observed the fluid surface in the brake fluid reservoir while an assistant sank the brake pedal. the surface remained undisturbed, indicating that the master hydraulic piston is not leaky. took it to the dealer. the sales & service managers observed but reluctantly admitted the behavior, tested it on their computer and declared it acceptable. i tested a second 2010 prius on their lot and the behavior was identical. consequences: having dealt with dealers before, we are unwilling to accept the dealer's reassurance for this seemingly unsafe behavior, and are now compelled to set the parking brake at every waiting stop. *cn

2010 toyota prius purchased on july 31, 2009. between 10 and 12 times since purchase date, when applying the brakes simultaneously with driving over a bump or rough section of road, the car felt as though it was accelerating rather than braking. this lasted for one second or less but was frightening. the first time i thought it was my imagination but it occurred another 10 times or so. it always occurs when going over a bump. as far as i can recall, the pavement was always dry. fortunately, there was no accident in any of these occurrences. *tr

My brakes quit working if a brake on loose gravel or when i hit a bump at low speeds. seems like the abs is trying to work but fails to kick on. *tr

My 2010 toyota prius has been having braking issues. it has happened 4 times that when i am stopping and hit a bump the brakes seem to not engage. *cn

2010 toyota prius software defect in the engine control system. consumer states while reversing before the start up operation is complete the brakes grab. *kb the consumer parked facing an upslope at the dealer to get his license plate installed. to leave, the consumer put his foot on the brake and pressed the power button. as the dashboard started to light up, he shifted into reverse, released the parking brake and the foot brake and started to ease down the ramp. as the consumer applied the foot brake, the brakes grabbed badly. the consumer released and re-applied them, and again they grabbed. the grabbing was severe enough that the vehicle was not safe to drive and the consumer just stopped. the consumer believed the behavior indicated a defect in the software that controlled the start-up sequence. the control computer should not allow the vehicle to be shifted into drive or reverse until the power-on operations have been fully completed. *jb

2010 toyota prius. car seems to surge forward when braking on rough pavement such as potholes. also happened once on a wet day when a front wheel slipped on the painted stop line before an intersection. we took delivery of the car in june 2009 and the first incident was in july 2009. *tr

Tl*the contact owns a 2010 toyota prius. the contact stated that while driving 10 mph and engaging the brake pedal, the vehicle briefly accelerated on its own and the brakes malfunctioned. the failure has occurred 10 times since the vehicle was purchased. the dealer was contacted and they stated that was a safety feature. no repairs were made to the vehicle. the failure mileage was 500 and the current mileage was 4826.