What 160 owners told NHTSA about the 2015 Toyota Prius Phev

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.

NHTSA ODI 11710539

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

NHTSA ODI 11706188

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.

NHTSA ODI 11705276

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.

NHTSA ODI 11705297

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.

NHTSA ODI 11701992

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.

NHTSA ODI 11698628

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.

NHTSA ODI 11698242

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.

NHTSA ODI 11697182

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.

NHTSA ODI 11697250

I was driving from Las Vegas to my home in Los Angeles. An alarming message began flashing on the dashboard telling me to pull over. The vehicle became hard to control. I somehow managed to get it off an exit. I was "lucky" enough to get it towed to a nearby Toyota dealership where I was told the inverter had failed and that that inverter and associated parts had to be replaced. On my 2015 Prius with only 50,000 miles on it. I SPECIFICALLY asked if there had been a recall on the electrical system of any 2015 Priuses, and they flatly said no. I also CALLED TOYOTA, and they also said there were no recalls involving the electrical system or inverters. The Barstow Toyota dealership said it would cost over $5,000 to repair AND that they wouldn't have the parts they needed for a WEEK. As it was, I had been stranded in the desert at a hotel for two days. I then had to pay $1,100 to be towed back to LA and took it to a hybrid mechanic I trust and paid them to do the work. But this cost me THOUSANDS UPON THOUSANDS. In a month where a friend of mine died (which was the reason I was driving from city to city). To have to replace this on a car with only 50,000 miles is preposterous. To NOW find out there actually IS a recall on the 2015 Prius FOR the electrical system involving the inverter is so far beyond frustrating, I don't have the correct word for it.

NHTSA ODI 11695550

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.

NHTSA ODI 11690972

Brake Accumulator and Master cylinder has failed. All lights for the ABS, TSC, and VSC are iliuminated

NHTSA ODI 11690363

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.

NHTSA ODI 11689781

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.

NHTSA ODI 11688952

The contact owns a 2015 Toyota Prius. The contact stated that while driving at various speeds and depressing the brake pedal, the brake pedal went to the floorboard, and the vehicle hesitated while responding. The traction control, ABS, BRAKES, and cruise control warning lights were illuminated. The vehicle was taken to Gasket Masters Inc, where it was diagnosed and determined that the ABS assembly was leaking fluid into the braking system, and the ABS module had failed, causing the brake pump to fail. The vehicle was not repaired. Additionally, the malfunction warning light was illuminated. The vehicle was taken to the dealer, but was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 186,000.

NHTSA ODI 11688356

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).

NHTSA ODI 11688213

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 (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11684838

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.

NHTSA ODI 11682496

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

NHTSA ODI 11679891

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.

NHTSA ODI 11679896

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.

NHTSA ODI 11678377

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.

NHTSA ODI 11677243

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.

NHTSA ODI 11676730

I am having a hybrid propulsion system issue due to a part that was recalled according to this ID number for the NHTSA 17V718000 that was posted NOV 14, 2017 and my car does seem to be affected because it is facing the same issues as other cars reported from that batch. I want to make sure that I can have it serviced properly at my dealership

NHTSA ODI 11676437

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)

NHTSA ODI 11670795