general problems of the 2015 Toyota Prius - part 1

Abs braking system suddenly not working. Abs, brake, and traction control lights all turned on.

Toyota Prius has a known problem with the brake actuator and booster. A notice was sent out in 2019 under the customer support program expansion with repairs up to 10 years or 150k miles. This is a safety issue and should be covered under a recall with no time or mileage limits since these problems are not showing up until after 10 years if the car has low mileage, as in our case. We just passed the 10 year mark, but only has 114k miles. No mention of repairs needed were made during regular maintenance visits with Toyota. Additionally, preventative repairs were not offered if the vehicle did not seem to be experiencing problems at that time. The brakes are spongy and unresponsive. The abs light , traction warning lights, and parking brake lights are staying on.

On 4/16/26, while driving my 2015 Toyota Prius (approximately 87,000 miles) on the freeway, I applied the brakes while transitioning from the [xxx] onto the [xxx] . As I veered right on the curved onramp, the brakes failed to engage properly, causing the vehicle to spin out of control and collide with the side railing. There were fortunately no nearby vehicles on the 2-lane onramp at the time. Under slightly different circumstances, this incident could easily have resulted in serious injury or death to myself and/or others. No airbags deployed. Although I was physically unharmed, I was extremely shaken by the incident. Immediately after the collision, the brake warning light, abs warning light, and another warning indicator illuminated on the dashboard. Prior to the incident, I had not experienced braking problems severe enough to suggest imminent failure. On 4/17/26, I brought the vehicle to Toyota of cerritos for diagnostic evaluation. I was informed that the brake booster was the issue and that the vehicle was unsafe to drive. The vehicle was towed to a collision repair center affiliated with my insurance company. After repairing the external collision damage, the collision center informed me that the brake booster malfunction that caused the incident could not be repaired there and would require dealership service. External repair alone: $3706, in addition to increased automobile insurance premiums expected over the next 3 years. I also contacted Toyota motor corporation regarding customer support program coverage related to brake booster issues and was informed that the program expired in 2025 and no assistance would be provided. I am submitting this report because this brake booster malfunction created a serious and unexpected safety hazard resulting in loss of vehicle control on a freeway interchange. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

My brake actuator and brake booster are failing. All of my dashboard lights have come on (brake, abs, traction control, brake system warning light). Unfortunately, I am over 10 years and Toyota is saying that I need to pay out of pocket for the repairs. This is a known problem and should be covered. I was unaware of the known issue and my car didn't start having problems until after the 10 year mark. I am under 150,000 miles.

Toyota Prius abs brake pump actuator booster failing making hissing noises and warning icon at only 10 years 9 month, 85,000 miles. Toyota extended warranty is not covering.

Brake booster and abs, brake master cylinder went out in car without any lights or warning while driving the vehicle at a moderate speed on freeway. I was able to avoid an accident and take the car to a repair shop in which at 119k miles and just at 10. 5 yrs old the entire brake system had to be replaced/repaired.

On Feb. 19, 2026, I went to an auto repair store to change oil. I was told that I need to have rear brake pad and rotor replacement service because my car does not have it. The mechanic showed me and said that I only have the front brake work and it can cause safety issue.

The brake booster suddenly fails at 54k mile. Brake responds slower and need to push the brake pedal all the way it seems a lot of 2010-2015 Prius are facing this problem abs light, skid light, and brake light was on when it happened, first appeared on Feb 6, 2026 have to replace brake boost for ~$1500.

Inferior brake system on 2015 Prius master brake cylinder and vacuum booster. Extended warranty issues identified by Toyota for 10 years or 150, 000 miles. I bought my Prius used in 2021 with 92,000 miles at age [xxx] old intending it to last as long as I did. I am now [xxx] old and essentially totally independent. The above mentioned parts were identified as not functioning properly on 2/3/2026 (mileage 139, 106). On 2/6/26, I took it to goettle Toyota, ocala FL (mileage. 139,160) knowing there was an extended warranty program available that was admitting the parts were defective but not worthy of recall. I was advised the warranty for my vehicle expired 10/26/2025 (3 months and 8 days prior) and was now invalid. Brake replacement cost is $3675. 00 + tax??. I was provided warranty information and instructed to call Toyota. I called, spoke with brook and was advised the warranty was invalid due to date even though the car has less than the 150, 000 mile covered and nothing could be done. I was never notified of this issue so I could monitor for problems before the expiration. Average life for these items on a Prius is 250,000 miles, not 139, 000. I am on limited, fixed income and cannot afford this unnecessary repair. I am already gladly driving a 10 year old car to be independent. Loss of transportation changes my entire lifestyle. I cannot afford another car (if I could, I would be fixing this one). I would be reliant for the rest of my life, on others for all needs outside of my home. I live in a very rural area. I feel since I was never notified of any issues and the car is low mileage and there should be another 100,000 miles on this car (I have driven it less than 50,000 miles in 5 years) that Toyota should honor the extended warranty based on the proximity of the malfunction to the ending of the warranty period and the low mileage of the vehicle. This amount of money is nothing to Toyota but it is life changing to this, up until now, independent woma information redacted pursuant to the freedom of infor.

Defected brake booster hard brake suddenly car less than 100 000 miles many vehicles with the problem.

I purchased a vehicle a year ago whenever my vehicle was still under the tenure and the 10 year and it’s still under 150,000 mile range. The vehicle was purchased strictly from the Toyota dealership in lakeland, florida, and shortly thereafter my brakes completely went out and the booster actuator assembly looking it up by further realize that is a very common issue and that there is so much that there’s class action lawsuits and also instead of it having a recall, it has a customer support to replace parts. My car is very dangerous and doesn’t have any brakes and it’s still very new from the dealership. What it’s very interesting is that it’s not throwing any codes at all, though it beeps the entire time that I’m in the vehicle with the abs light on and I know that it’s that problem why is it not showing any codes I think that for sure, the dealership would’ve had to done something to prevent that in order to sell the car unsafely.

The abs failed while driving on the highway. There was no accident, but it was substantially harder to brake when needed.

While driving, my brakes became mushy and ineffective. Brake warning lights came on, also. It was very scary driving in rush hour traffic with little to no brakes. There was no reliability. Just keeping as much as possible space between cars, using hazard lights &prayer.

The vehicle has 95k miles on it and both brake actuator assembly and booster pump have gone bad. This is a defective issue, I called Toyota and was told too bad since the program that fixed this ended 02/25. The car met the mileage requirement, but being 10 months out of the date gives Toyota the right to wash their hands on a defective part. The part is over $1500 just in parts to replace! this is wrong on their part. Not one option offered.

This vehicle has 95k miles, now the vehicle has a brake problem which can cause deadly problems. The parts that have gone bad on this car are defective parts that Toyota knows about. The warranty they extended for this ended in 02/2015. They had 150k miles or 10 years limit on that warranty. We are well under the mileage and 10 months over according to Toyota. Can’t believe they will dismiss something this delicate and dangerous. The parts are not cheap and it’s something we can’t afford to fix right now. I can’t believe Toyota will just wash their hands on something this important in a vehicle. This is a know defective part! they should have some sort of responsibility and resolution. I called and was told they cant do anything. Even a part offer so we can fix nothing. Please review this and hopefully you can help.

The brake accumulator went out thanksgiving day on my way home nearly causing an accident. I also missed dinner due to the issue creating a clearly unsafe driving condition where I was barely able to use my brakes. This is a known issue by Toyota, whom extended the warranty to 10 years. Of course, my warranty was 3 days past the 10 years even though it is under the mileage requirement. This should have been a recall, as it is a known and reported problem. I am now out 3300$ for the repair just to get my car in an operable condition. There were no warnings, the abs light as well as the traction alert went off and I lost the ability to properly brake in an instant. There was no warning, nor was I notified about this part.

The abs, break, and traction control, suddenly turned on when I was traveling on the freeway in mild traffic. I was traveling at about 60-65 mph. I attempted to use the breaks and could feel a substantial difference in how much and how hard I had to push in order to stop. The problem has not been confirmed by a dealer or service center. The vehicle was inspected by my brother in law who works on cars frequently. There were no warning symptoms prior to the problem. The problem first occurred on Saturday November 1st at about 12:30. According to my brother in law, it was the break pump that failed; you can hear air escaping when you push on the break pedal.

The contact owns a 2015 Toyota Prius. The contact stated that while driving approximately 15-20 mph, the abs, brakes, and the traction control warning lights, and the malfunction indicator light were illuminated. Additionally, the vehicle hesitated to respond while depressing the brake pedal, causing the braking distance to be extended. The vehicle was taken to the dealer, where it was diagnosed with an abnormal leak in the accumulator and a leak in the brake booster pump. The dealer determined that the brake master cylinder and the brake booster pump needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 94,100.

Emergency brake, traction and abs warning came on and stayed on in addition to a five-second interval cycling on of a motor sound under the hood. O'reilly auto parts and then Toyota dealership confirmed the same code that indicated brake booster assembly needs replacing (c1391) **this is a "known issue" but not yet a recall. Toyota did extend the part warranty to 10 years or 150,000 miles - my vehicle has only gone 85,500 and unfortunately is eight months into the 10th year and Toyota is refusing to cover any portion of the repair. I would like to be part of the effort to have this formally declared a recall because I got the quote today to replace the brake booster assembly and it's going to cost half the value of the vehicle! $4000 is the low estimate bighorn Toyota gave me to do the repair/replacement. Thank you for your help!.

Brake accumulator and master cylinder has failed. All lights for the abs, tsc, and vsc are iliuminated.

Got the warning code for c1391 for the brake booster. It failed at 140k miles but because it failed past the 10 year mark did not qualify for the Toyota extended warranty program. I don't think the warranty program is good enough and should be addressed as a recall. I had sudden total brake failure on the highway which could have been extremely deadly.

On or around 9/13/25 my abs, brake, traction and emergency sign sensors turned on in my 2015 Toyota Prius. I noticed that my brakes became squishy and when I drove, it took longer for my car to brake (there was more distance in my braking ability to stop the car). My car also felt a bit more airy than it usually does when I drive it. I took it to 2 independent car repair shops for a diagnostic and both told me that the abs c1391 code came up. Soon thereafter, I took it to a local Toyota dealership for a diagnostic and was given the abs c1391(code) abnormal leak in the accumulator. The Toyota mechanic informed me that that when he did the diagnostic, the TSB 0024-19 code came up on his end, which means that Toyota alerts their mechanics of the necessary procedures to implement for this problem, as it's a known Toyota problem and defect: 1) remove & replace the brake booster assembly w/the master cylinder (apparently the master cylinder goes out too since they're connected) and 2) remove and replace the brake booster assembly pump. Toyota's estimate to repair it is $4,404. 72; I can't afford this and need a car. It's my only car! I did research and learned that this is a known Toyota issue for Prius (2010-2015) and a customer support program w/an extended warranty was issued to cover the full cost. Despite this, their extended warranty expired for me on 12/29/24, despite me meeting the other 10 yr or 150k or less mileage criteria. Despite filing a complaint with Toyota's resolution center they refused to extend or offer warranty or any payment for a known Toyota defect, saying my issue was "after the extended warranty date" and there "isn't a recall. " I'm disgusted to say the least about this, as Toyota is well aware of this car part defect which is a safety hazard and liability for its customers. Something must be done about this. It's unfair and not equitable to have loyal Toyota customers absorb the cost of known safety hazard defects by Toyota and risk lives.

The brake booster system failed two weeks after the Toyota customer confidence program for that condition ended and they will not reimburse me for a $3000 repair. I knew there was a problem because all the dash lights came on at once while we were driving on a highway. I had it towed away to be repaired and it was found that the brake booster system was failing. Had I ignored it or not acted as immediately as I did the brakes could have failed while the car was in use and hurt or killed me or someone else. They should issue a recall for this condition and fix it for Prius models that still need it and they should reimburse me.

Before, I was driving and occasionally the traction control light would flash when I put my foot down on the brakes but would go away when released. I didn't think much of it but then a few days later, I went to brake to stop the car and then the abs, traction control and brake system lights lit up on the dash and wouldn't go away. I pulled over safely and turned the car off and on again but it wouldn't go away. The brakes were also noticeably more firm compared to before as it was quite squishy but now it was solid and all regen braking went away and it appeared I had no more abs which could lead to a collision. I immediately took it into the dealer to have it diagnosed. I did some reading and if I kept driving with this problem, eventually the brakes would fail and collapse completely and leave me unable to stop the vehicle. At the service center, they were able to read the code dtc c1246 and clearing the codes did not work. The part that was replaced was the brake booster and the brake master cylinder and the brake pedal stroke sensor. It appears that a warranty program exists for this issue but it is not a recall. I am also not sure if the part that was replaced is a revised part that will no longer have this issue or there is no change in the part design. I believe this is a massive safety issue and should be a recall and not a warranty replacement program as every Prius should be recalled for this defect. I was very close to being out of warranty and if I had taken any longer to bring it into the dealer I would have been out of the extended csp warranty. Even the dealer initially thought I would be out of warranty but I had to argue that I was in warranty and should be eligible for a warranty replacement and that I should not need to pay for a diagnostic fee despite it not being a recall.

I have a 2015 Toyota Prius with 48,600 miles. My breaks started failing suddenly while driving which almost got me into a car accident. I took it to my mechanic immediately and the dtc was code c1281. I was advised to take the car to a Toyota dealer. I got an appointment and a manager was waiting for me wanting to charge me $250 for a new diagnostic test and $2,500 - $3,000 for repair if the diagnosis was correct. I called customer service and washed their hands from any responsibility. I called the Toyota's customer advocate service located in plano, TX and was on the phone for more than an hour. They apologize, were very courteous, but I was told that I was not covered because I had call too late and that the repair offered by Toyota had expired. They acknowledged that Toyota never issued a recall for this manufacturer defect. I informed them that the discovery of the problem had occurred on [xxx], 10 years and 2 month after I bought the car from them and that the car was almost new with very little mileage. I let them know that felt this was a deceptive trade practice with breach of warranty and breach of implied warranty of merchantability, along with it being a fraudulent concealment with failure to warn their customers of potential danger and harm. I plea with the Toyota's advocate that since the statute of limitation and equitable tolling had not elapsed from the day of discovery that they should honor my request for it being just. I was told that Toyota's decision on the Prius brake defect was not covered and that I was free to take my car to a Toyota dealer or an independent mechanic, whatever was more convenient and/or affordable and that the cost was on me. I asked if I were to get a new Toyota car and trade in my old car if they would appraise it as if the defective brake part had not malfunctioned. The answer was that the value of my car if traded in, would be significantly less due this issue. He gave me a ref # [xxx] and hanged up. Information redacted pursuant to the freedom of information act.

Our 2015 Prius suffers from the brake booster/master cylinder defect as outlined in TSB t-sb-0024-19. Which is a well known an pervasive issue for this vehicle. We were unable to medically drive when the vehicle was still under the time frame and mileage which would have allowed it to be covered by Toyota. Despite requesting an extension due to extenuating circumstances (medically unable to drive, thus detect the issue during the covered period) they disclaim any and all remedy. When I was able to drive the vehicle after being cleared from surgical recovery restrictions, the issue was immediately found and reported to Toyota whom promptly denied the claim through their local dealership and subsequently through their offices after sending a letter requesting an exception or good will extension. This issue is a major safety issue and unfortunately also a cost prohibitive repair to take on. The defect in question is acknowledged by Toyota through multiple TSB's and warranty extensions and their own zjb customer support program. We are under the actual mileage cutoff but outside the time frame by a few months (medical period where the vehicle was not driven).

Code c1391 leakage in accumulator abnormal. This required replacement of the master cylinder, brake booster pump assembly. This fault resulted in mushy brake pedal and loss of abs system. The components were replaced at a Toyota dealership. Total cost was $3207. 82. Apparently this was a known issue with Toyota for Prius models 2010 through 2015.

The brake booster pump and abs actuator is beginning to fail recently. I took it to the Toyota dealership to use customer support program zjb to replace the parts, but they said my vehicle was not covered. They then quoted me $3000 to fix the issue. The brake booster pump and abs actuator contribute to safety while driving, so why is this not recalled? we need an official recall to happen and not a simple customer support program.

Brake booster failed. Abs lights on. Brake light on. Traction control light on. Was sitting at stop with foot gently on brake when lights turned on. Attempted to restart car to clear lights, lights would not turn off after normal restart x3. Brake no longer function correctly, and the factory installed abs are no longer functioning. Braking distance greatly increased, and no longer as safe to operate.

Failure of the: pump break booster actuator had it towed to Toyota and they said it’s a $3,500 repair.

2015 Toyota Prius abs warning light came on . Went to car mechanic . Brake actuator & pump code leaking. It happen on 7/27/25 under 100,000 miles. Currently anti sway and abs braking disable.

While driving my Prius on the highway, the abs and traction control warning light suddenly came on. The brakes started feeling different right away, and it didn’t feel safe to drive. I took it to a Toyota dealership, and they found that the brake booster and pump had failed. I looked online and saw that many other Prius owners had the same issue, so it doesn’t seem like an isolated case.

Hi, I am reporting a brake system failure on my 2015 Toyota Prius. In July 2025, the abs and brake warning lights suddenly appeared, and a Toyota service center confirmed it is the known Prius brake system defect. The repair estimate ranges from $4,502 to $27,814, but Toyota declined coverage because the vehicle is just past the 10-year warranty limit. This issue poses a safety risk due to reduced braking performance. 1) the brake system / abs actuator assembly malfunctioned. And yes, the component is still installed in the vehicle and available for inspection upon request. 2)the abs is no longer functioning properly, significantly increases the risk of losing control or extended stopping distance, especially in wet or emergency braking conditions. I rely on this car for daily transportation in a car-dependent area, so this issue directly affects my ability to drive safely and could endanger others on the road. 3)yes. The issue was diagnosed and confirmed by an authorized Toyota dealership center. 4)yes. The vehicle was inspected by an authorized Toyota dealership only. 5)yes. The abs light, brake warning light, and other dashboard indicators suddenly appeared in July 2025.

Brake light + abs + traction light came on and the brake became harder to control. I was driving in the rain and briefly lost control. Fortunately, no accident.

Omponent/system involved: service brakes, hydraulic ? make: Toyota model: Prius year: 2015 mileage: 155,470 VIN: [xxx] ? what happened: my 2015 Toyota Prius is experiencing brake failure symptoms related to a known defect addressed in Toyota’s warranty enhancement program zjb. The vehicle has triggered dtc codes c1256 and c1391, which indicate failure of the brake booster and master cylinder — a problem widely reported by Prius owners. The defect causes decreased brake effectiveness and increased stopping distance. My Prius is just 5,470 miles over Toyota’s 150,000-mile coverage cap, and despite confirming the exact codes, the dealership refused to repair unless Toyota pays first. Toyota corporate opened case #[xxx], but has not offered a resolution. This is a safety-critical issue that Toyota acknowledges in internal service bulletins, but they are denying assistance based on a technicality, despite my vehicle having the exact failure their program is designed to address. I am filing this complaint because I believe Toyota is avoiding responsibility for a dangerous manufacturing defect affecting braking performance and safety. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).