Automatic Emergency Braking Problems of Toyota Prius - part 2

I went to several mechanics and got the same issue confirmed. It is a booster brake system issue. I called consumer advocates and they said the notice went out in 2019 and since then expired. Therefore dealership is not going to repair the defect. I received no such notice. When I contended that this is a safety issue and should immediately be handled and my car has 80,000 miles on it and it has not even been 10 years they refused. From my research I see that it is a wide spread issue with the break booster and deffinately warrants a recall. I am disabled and have many medical issues I need money for and can not afford $3000 manufacturing fault defect is not my responsibility.

See all problems of the 2014 Toyota Prius 🔎.

The abs pump( accumulator and booster) are regularly failing on all Toyota Prius( 2010-2015). When the abs pump starts to fail, the warning lights for traction control, brake and abs come on. These lights come on at all speeds and its very hard to bring the vehicle to a complete stop when this happens. The brakes completely stop working and the brakes become rock solid. The brakes become so hard that they can’t be possibly be depressed to stop in time. I nearly missed getting killed from this as I am out of country and Toyota is refusing to fix it since its not a recall and I am in canada. Toyota is asking $3500 in parts and $1500 in labor to repair. I can not afford it and this issue is on all Prius from 2010-2015. This is a major safety hazard and can cause serious injury and damage. Toyota is refusing to repair it since they believe the cars are out of warranty. However Toyota has been notified about this safety hazard arising on all Prius(2010-2015) but decline to respond or take action. I urge NHTSA to take action and get this resolved as the abs brakes failing on the Prius can be really dangerous and can cause life threatening accidents.

See all problems of the 2010 Toyota Prius 🔎.

Four warning lights related to the braking system illuminate, followed by what seems to be the cessation of the abs. After 5 minutes of driving, the lights went off and abs returned, although brakes are shaky. The abs seems to be a known faulty park and is covered under warranty but only up to 150,000 miles. When taken to a dealer, the repair shop recommended I call corporate. Citing the arbitrary mileage limit, the Toyota mechanic seemed convinced the corporate office would cover the cost, saying he’s seen it done on a case by case basis. This coverage should be made unilaterally for all car owners with this defect, not simply those willing to fight for it. Class action lawsuits over what seems to be a similar issue have been privately settled.

In the 2009 Toyota series ii vehicle there are two parts for the brake actuator pump assembly which has been cycling about every 20 seconds for the past six months or more. There is an intermittent tone when depressing the brake pedal before starting the car (engine off). The brake dash warning light is on continuously. Occasional loss of brake power in reverse causing the driver to re-apply the brakes to stop unwanted motion of the vehicle.

See all problems of the 2009 Toyota Prius 🔎.

I was idling at a parking space and went to turn off my car. The vehicle surged forward and the brake sign came on. I pushed my brake to the floor and nothing happened. I was moving toward a brick wall so I put in in reverse and the car surged backwards. The brake sign came on and I pushed the brake to the floor and again nothing happened and I ended up hitting the car behind me. I immediately took my car to the dealership where they kept it for 3 days and said they could find nothing wrong and it was safe to drive. I just got it back from having the body work done and am afraid to drive it as this might happen again or worse. I am reporting it to let you know and to see if this has occurred and been reported as happening in this make and model previously. I also have 2 witnesses to what happened.

See all problems of the 2019 Toyota Prius 🔎.

I was driving when I felt my brake pedal start to become soft and mushy. I was able to brake, but I had to pump the brakes to get full brakes to stop. I also noticed warnings began to appear on my dashboard. The warnings that were shown are the brake light, traction assistant light, and abs light. I took it to gates Toyota in south bend, in and paid for a brake inspection. They told me that my brakes themselves were ok (pads, rotors, calipers), but they were getting a c1391 error. I was told that the brake accumulator has an internal leak. I was told that I needed to replace the brake master cylinder and brake booster pump assembly. I bought the car used from the dealership about a year and a half ago. After doing research, I found that this same issue has been a common recall problem on a number of Toyota vehicles starting as far back as 2008. I also found a few class action lawsuits concerning Toyota vehicles with the exact same issue. My vehicle doesn't show any current recalls, but I'm having the same problem as other Prius v vehicles are having. I was quoted $3300 to fix this problem. I shouldn't have to be responsible for paying for a defect that has been recalled on a very large number of vehicles, and also has been the result of class action lawsuits.

See all problems of the 2012 Toyota Prius 🔎.

Code c1391 - abnormal leak in accumulator. Accumulator for the brake pump is not holding pressure so the pump has to keep turning on to refill. Brake pump and abs unit have to be replaced. In emergency situations, a malfunctioning abs module leads to increased stopping distances and loss of steering control during hard braking. Lastly, tires can be worn more easily, which could lead to tire blowouts. This puts myself and others at risk for deadly consequences due to an increased chance for collision if I am unable to control or stop my car. This problem has been confirmed by Toyota and multiple years of Toyota vehicles have had their brake actuator assembly warranty enhanced. The warranty enhancement program has secondary coverage, which is applicable for 10 years from the first date of use, or 150,000 miles, whichever occurs first. Currently I meet the 10 year requirement but have 162,000 miles on my Prius, which is completely frustrating. Many have posted with the same problem of being just outside the warranty. The vehicle has been inspected at a Toyota dealership. A symptom was noticeable starting from over 1 ½ years ago when I was under 150,000 miles. The car produced clicking sounds when the brake pedal was held down at traffic lights. Once released, the clicking sound would stop. I spoke with a Toyota mechanic and he told me it was an issue with the brake pump and abs unit, but Toyota would not repair it until it completely failed. He also mentioned that there was coverage available for the abs unit once it failed as it was a common issue for the Toyota Prius. If Toyota warranty allowed for the brake pump and abs unit to be replaced when the symptoms appear instead of when it completely fails, I would have qualified with my mileage. Not only is the repair costly, but for those who cannot afford it and need to continue to use their car despite the brake pump and abs unit failure, risk their own and others safety when continuing to operate their vehicle.

The 2011 Prius has an issue known to Toyota, in which the brake booster pump fails after an indiscriminate amount of time, leading to significant loss in braking ability and control. Toyota knows of this because they issues an extended warranty coverage for these vehicles and this issue, that did not extend beyond 10 years, or 150,000 miles, whichever comes first. (https://static. Nhtsa. Gov/odi/tsbs/2019/mc-10164923-9999. Pdf) when I was driving my car down highway 183 I lost braking control completely, with a series of constant beeping starting to emit from the braking system. Luckily through mashing the brake pedal and using ebrake I was able to get the car to slow down and pull off the highway. The brakes sporadically and randomly cut in and out with the power braking, leading to uncontrolled stopping power and jerky or inactive braking. There had been lights on the dash indicating the traction system or braking system had issues but these would frequently turn off and on and didn't result in a loss of braking ability or performance and had been there a couple months. Upon taking the vehicle to a Toyota dealership (charles maund north austin) I was told it was a c1391 error regarding a failure of the brake booster pump assembly and that it would need to be replaced and reprogrammed for about 3300 dollars. After looking online I saw there were many other people with this issue, all who were unable to fix this in the given 10 year frame. Many unsuspecting second owners of this vehicle do not know that there is a hidden danger waiting for them when their power brake pump assembly fails. If I had been a less experienced driver I would've certainly crashed and Toyota, knowing of this safety concern already, should have done the right thing and issue a recall for these vehicles.

See all problems of the 2011 Toyota Prius 🔎.

There was a driver side collision and the airbags did not deploy. Brakes do not slowly apply they slam down causing vehicle to slide/skid in emergency braking, abs does not function properly. The dealership recently did an appraisal (4/2/25) on the vehicle that states “lost communication with side airbag sensor lh, side airbag sensor lh initialization incomplete, front speed sensor rh & lh circuit, and d- door motor ecu communication stop”. Insurance company inspected vehicle after crash, and there was a police report filed. There were no warning indicators prior to incident or after.

See all problems of the 2013 Toyota Prius 🔎.

I have had a 2012 Prius since 2016. The entire time I've had it, it occasionally "hydroplanes" but without any water. It happens in wet or dry (but mostly dry) conditions. Usually at slower speeds so, though it makes me very uncomfortable, it doesn't happen with any regularity. I've taken it multiple times to my mechanic who always says "prius' just do that", which is not reassuring. I know there was a recall and I was told my car did not fall under that umbrella. On Wednesday of this week, 10/25/23, I finally had an accident because of this. The brake lockup had been happening more frequently in the past week and in this instance I saw the car in front of me suddenly slow down - I had about 2/3 of a cars distance between me and the car ahead. I hit the brakes and nothing happened. I was pushing down on them long enough to think, "ok, this is it. They aren't responding at all and I'm going to hit this car in front of me. " I did and it crushed the passenger side of the car. Luckily I wasn't hurt. There were no warnings from the car at all that this was going to happen, as there never are. I took it in for possible repair today (the mechanic is not sure but thinks it may be a total loss). This car did everything they describe in the recall cases and I want to know if there's anyway to be repaid from the company for this as there was nothing I could do to stop this accident? why wasn't my car included in the recall?.

Error code c1391 confirmed by two separate facilities, described as "abnormal leak in accumulator" and "accumulator pressure. " took to an independent shop first, then to haley certified Toyota dealership. At dealership, parts needed were quoted to include TSB-0024-19. Three lights went on simultaneously (abs, traction, brake).

8/2/22 my abs light came on. Took the car to a dealer. They kept it for six weeks and returned it on 10/3/22. No charge and no explanation. 11/7/22 engine light came on. Took in to dealer, they returned it 11/17/22 indicated incorrect air/ fuel mixture. 10/9/23 traveling 47 mph, came around a mountain and encountered stopped cars. Slammed on the brakes, car did not slow down, steering wheel locked to the right, car yawed to the right, and turned over, hit a curb and the car righted itself. 3 occupants, 2 injuries , 1 death. Researching the 2012 Toyota Prius, found many instances of a faulty abs system, mimicking exactly my experience. I was never informed by Toyota or the local Toyota dealer.

Since October 2023, my 2019 Toyota Prius has developed severe and unpredictable driving behavior after a regular brake service, which may have triggered or coincided with a software or ecu update. The car, which had been driving smoothly since I bought it in 2021, suddenly began showing false braking, steering interference, and lane instability — as if the car were trying to “correct” problems that didn’t exist. These interventions often happen on highways or during turns, creating serious safety risks for both driver and passengers. I’ve spent months and thousands of dollars replacing parts, performing alignments, and recalibrating sensors, including at Toyota dealerships. The problem persists because it is software-based, not mechanical. I discovered that in mid–2023, the NHTSA announced upcoming rules requiring automatic emergency braking (aeb) with pedestrian detection by 2029. Around that same time, reports from multiple drivers (Toyota, Honda, Hyundai, Ford, Subaru) began to appear describing the exact same issues. It seems manufacturers began silently updating vehicles to meet anticipated compliance standards. However, this introduced overly sensitive and malfunctioning driver-assist systems. The most alarming part is that the driver cannot fully disable these features — the “off” button only reduces their intervention. This means when the system malfunctions, the driver is forced to operate an unsafe vehicle. As a professional rideshare driver, this problem destroyed my ability to work. Passengers reported me for unsafe driving because of the car’s erratic behavior. I eventually lost my vehicle and income. I believe this is a systemic safety defect linked to premature or unregulated implementation of aeb software. Drivers deserve the right to fully disable malfunctioning systems that endanger lives. This is not just a car issue — it’s a public safety crisis that must be urgently investigated.

The brakes fail and the abs module stops working correctly and when I go at a speed of 60 mph the brakes lock until the speed drops and they work again. The problem is with the abs module and I went to the dealer and the repair value is $3450 dollars.

2012 level 5 plug-in I was driving on the freeway with radar cruise control and the vehicle dash lit up with check pcs system ever warning light came on the brake petal was not there as normal it would go about half way down to engage very scary I took it to the dealership service said I need new brake booster installed not covered under warranty 130k miles.

Affected by the recall number 10v036000, the 2010 Toyota Prius is manufactured with a defective brake booster and master cylinder system which causes defect of the brake system, and causes my vehicle to often lose power in abs and randomly lose abs power braking, making brakes hard, and makes for longer stopping distance. This is a problem for many and obvious reasons on the road regarding safety. All vehicles should have optimal braking systems for the road, and should otherwise be repaired at no cost if the car is manufactured with defect. This has caused no accident for me yet but the abs has failed on many occasions. I have read at least 100 cases of this given vehicle under this recall being caused an accident with faulty brakes, and sometimes complete failure to stop which is extremely worrying. This recall excludes VIN numbers past a certain date, yet the recall in question is certainly still affecting many cars, as capistrano Toyota has also called for petition of Toyota to repair at no cost for all affected vehicles. Yet all dealerships have denied my request and Toyota has no formal coverage regarding the rest of the faulty vehicles they manufactured.

My teenage daughter was driving and almost had an accident because the brakes failed. No warning lights came on until the brakes failed. I am learning now that it is a brake booster pump that Toyota knows about it as they had issued an extended warranty on the same thing that expired last year. Toyota confirmed that my pruis was included in the customer service program but it has now expired.

The car was being driven on us287 south from wichita falls, TX toward fort worth, texas on an open road, in the middle of the afternoon, in clear sunshine, no clouds, no rain. On a stretch of the highway where the road dipped down into a gully, and had a normal rise afterwards, the automatic braking system activated, gave a warning of an impending collision and applied the brakes to stop the car hard. Luckily, there was no traffic ahead or behind the vehicle at the time of the incident. The car came almost to a stop before it realized that there was no danger ahead of the vehicle and the automatic braking system released from the emergency situation at about 5 mph. If there had been cars on the highway following the vehicle, it is doubtful that they would have been able to slow down in time to prevent a rear end collision. The vehicle was slowed down in a maximum breaking action on an open highway, with an open road ahead of the vehicle. The system interpreted a hill ahead of the car as a danger to be avoided.

See all problems of the 2023 Toyota Prius 🔎.

Have an issue with the Prius having the error code c1391. The dealership refuses to fix the issue since it's unsafe to drive with the brake failing. Need to replace the brake power booster and abs pump/ motor; the total cost to get all this is quoted by the dealer as $3300.

The abs sensor on the brakes failed while driving on the highway. This could have caused an accident. These modules should last the lifetime of the car.

See all problems of the 2006 Toyota Prius 🔎.

Three lights appeared on the dashboard…code c1391. This has affected the braking system, and the traction control…and the brakes no longer regenerate the battery. The mechanic said “you must not drive this car” until a $2,700 repair is made. There was, apparently, a service bulletin sent out in 2019, and was then extended until 2022…which we did not receive, although we’ve been at the same address since we bought the car. But our car did not develop this common issue until now…2023, and Toyota says it was not a safety recall, so they don’t need to fix it, or help us get it fixed. We believe it is obviously a safety issue…. Since my brakes can go out at any moment.

My Prius 2010 has thrown the abs, traction, and brake hud lights all together. I took it to an autozone and scanned the code to get the c1391: abnormal leak of acc press error. Many Prius 2010 have this issue, I'm sure I'll need to replace the actuator and/or accumulator and I know that will cost a good bit, I hope Toyota could help us fix it.

The break booster started making a noise and my car should have fallen into the range of the previous recall for the exact part. I cant afford to change it so I continue to drive it and all of sudden the breaks are so hard to push and a constant buzz is going off! autozone confirmed it was the break booster ans abs then a private shop did also.

I noticed that my brakes felt mushy when applied. The abs light came on in my car. I took it to 2 different Toyota dealers and both said that my break boosters were failing and would need replacing. I had 125,000 miles on my car. The brakes were working adequately at that time, but I was aware that they could fail at any time and put me in danger. I was charged $3637 for diagnosis and repair on 12/6/22.

Attempted to park in my garage and overshot the turn. The brake then failed to stop and I dented my garage outer wall. I reversed my car and tried to reposition it to go inside the garage, putting it on drive. However, the brake pedal made the car accelerate and the car went on reverse. It then crashed into the neighbor's garage and crashed the door and car inside. Both the car inside the garage and the garage itself (along with the inside of the house) have been damaged.

See all problems of the 2020 Toyota Prius 🔎.

My breakes failed when driving. I almost got in accident. Code c1391. Brake actuaror failure. Car has 200,000 miles. Toyota is denying to repair the car. It is well known problem with that but still not fixing.

Brake, abs and traction control warning lights went on when I was driving. I was able to brake but it was not functioning at 100%. The local mechanic was able to scan the code to get the c1391: abnormal leak of acc press error. The warning lights remain when I drive or parked. I no longer feel safe driving my vehicle. I plan to take my car to the Toyota dealer for further diagnosis and repair. I was informed that this is a very costly repair.

While on the freeway, I was braking due to traffic and the car started shaking and the abs light, "brake" light and traction light all came on and remained on. The brake system did not operate properly, which nearly caused a collision.

While driving, left dash-light cluster and abs triangle illuminated in-traffic with no visual pre-warning or audible alarm. Pedal pressed full force to bring car to stop and not plow vehicle in-front. Owners manual & internet suggests abs & booster pump failure. Call to mechanic also suggests booster pump and abs module as possible basis for trouble lights. Arranging transport to Prius specialty shop (not dealer) for further diagnose. No collision no injuries. Note. Full service brake rotors & pads completed 27-days earlier and only 671-miles driven since costing $946 paid. No issues discovered by reputable Prius shop as to noise, leak or visual other. R.

Running errands and when I got back to my Toyota Prius v many lights were illuminated including my brakes abs tire pressure traction lights were all on. Tool my car to dealer for them to gladly request $5,000 to repair this. Dealership told me "the repairs are going to be a new master cylinder + new brake booster pump + fluids as needed for repairs" . This is a known issue for 2012 to I believe 2014 Prius model v. This is a huge safety issue and a manufacture error this should be recalled and covered by Toyota as shouldn't be any fault of my own. On today's world 5k is a crazy amount of money to fix a known issue thay could arise again. Toyota needs to do better to protect their customers. Shame on them.

All brakes warning light went on while driving. The anti skil, abs, emergency brake lights. The car was unable to stop and code reader indicated a brake booster pump and brake actuator/accumulator failure. The failure was confirmed, and the brakes just stopped working while driving. I almost crashed into another car as the brake was not working no matter how many times I press it. Contact Toyota, they are careless and said it was not cover in any recalls and an enhancement warranty just passed 4 months on my car. A previous voluntary recalls was issue for the car model year before mine. This is a fundermental feature of a car and should be fix regardless of age. It is putting people's lives in danger and will cause accident!.

The contact owns a 2004 Toyota Prius. The contact stated while driving 51 mph, the vehicle experienced phantom braking and a loss of power steering assist with the engine overheating message displayed. The vehicle was not diagnosed nor repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure. The failure mileage was approximately 154,079.

See all problems of the 2004 Toyota Prius 🔎.

The brakes abs stopped working. It is a known issue and is effecting many older Prius drivers.

The abs actuator is bad. Cant stop nor use the rechargeable braking. Very dangerous.

Vehicle brakes fails to stop and needs to push hard on brake paddle to stop the vehicle. Traction control light, abs, and brake lights come on. Took to autonation Toyota irvine in Dec. 2020 reporting the issue but the tech clear the codes and told me that nothing is wrong. The same light came back on and took to 3rd party shop and was informed code c1391,c1345 & c1368 reporting issue of a failed booster and booster pump. Customer support program zjd. I've been in contact with Toyota brand engagement to report the issue and regarding automation Toyota irvine clearing the codes after I took my vehicle to the shop for repairs. But dealer is not repairing the vehicle and the vehicle has been in the dealer shop since Jan 10, 2021. Reporting a issue with brake failure on my 2013 toytoa Prius.