Service Brakes Problems of Toyota Prius - part 2

The brake and pre collision system suddenly fail without warning.

See all problems of the 2010 Toyota Prius 🔎.

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.

See all problems of the 2015 Toyota Prius 🔎.

Upon inspection, our mechanic determined that the master cylinder assembly and the actuator assembly require replacement (error code c1391). It is currently available for inspection, but will need to be repaired soon. Our safety and the safety of others is at great risk, because there is impending brake failure if driven and the end result could be catastrophic. On 09/13/25, the brake, traction control, abs and ((!)) lights came on about 10 minutes from home. We drove home, parked the car and did not drive it again until we took it to our mechanic on 09/15/25. During this incident, the brakes failed to respond properly, which could have led to a serious accident. We took the car to a local mechanic and repairs are currently pending. The estimated cost for the necessary parts is approx. $3,000 and the labor costs are estimated to be between $1,100 and $2,000. Our local Toyota dealership was also contacted and they confirmed the presence of code c1391. Please reference Toyota service bulletin pol18-03, which addresses issues related to the braking system in certain Toyota models, including the Prius v. This bulletin indicates that various brake system-related warning lamps may illuminate due to internal malfunctions within the brake system, and it outlines affected parts that may require replacement. Additionally, please reference Toyota customer support program 20te07, which provides extended coverage for certain brake system repairs. It is concerning that, despite this well-known, very serious problem, Toyota has not issued a recall. While our vehicle currently has 116,975 miles, we are aware that the warranty period ended 10 years from the first date of use or 150,000 miles. However, this malfunction not only endangers our safety, but also that of other drivers on the road. We urge the NHTSA to investigate this matter thoroughly and consider the implications for a potential recall for this model, because Toyota is well-aware of this issue.

See all problems of the 2014 Toyota Prius 🔎.

I turned left into a parking space in my 2020 Prius. I stepped on the brake, and my car shot forward. I couldn't stop it, and it hit a concrete pole. It only took 1 second. It seems Toyota hybrids are still having this unintentional acceleration despite a multi billion dollar law suit in the early 2010's. My car was towed and is awaiting inspection by my insurance company. [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2020 Toyota Prius 🔎.

I have a 2013 Toyota Prius with 164,000 miles. A mechanic confirmed that the master cylinder and brake booster are failing and are not covered since warranty expired 14,000 miles ago. I have heard this is a common issue with this vehicle. Traction light, brake light and abs light are all on. The earring lights go on and off.

See all problems of the 2013 Toyota Prius 🔎.

My 2022 Toyota Prius (approx. 12,500 miles) suddenly displayed multiple warning lights while driving, made abnormal noises, and lost the ability to move. The vehicle remained powered on but could not drive and had to be towed to a Toyota dealership. The dealer diagnosed a failed brake booster with master cylinder assembly and quoted ~$4,230 for repair. This is a safety-critical component that should not fail at such low mileage. Toyota has previously acknowledged premature brake booster failures in earlier Prius models (2010–2015) and issued customer support program pol18-03, extending coverage to 10 years/150,000 miles for the same component. I believe my 2022 Prius experienced the same type of defect, but Toyota refuses assistance. A sudden failure of the brake booster system while driving poses a serious crash and injury risk.

See all problems of the 2022 Toyota Prius 🔎.

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.

When test driving the vehicle I asked about this buzzing/ whirring noise while sitting in the running but parked car. I was told these cars are hybrids, the electrical components make all sorts of whirring and humming noises and not to be concerned. Over the years I heard this noise, increasingly more and more, but I never knew it was something to pay attention to. Fast forward to July 2025. I noticed the car is inching forward while I’ve been stopped for a while at a red light almost like the brakes don’t want to hold. This has been happening so often that I have began to put the car in park while waiting for lights to turn green because it gets painful having to push the brake so far down. I take my car to a mechanic, explain all of the noises and the sensations and two mechanics drive it but say it feels fine and there are no recalls. They say my front brake pads are low and that must be what I’m feeling. After replacing the brake pads nothing had changed. Now there is also a squeak while moving at a slow speed in stop and go traffic. 1 week later I bring it up while getting an oil change and ask if they know what it could be. They said brakes seemed fine. A couple weeks go by and yesterday while I was driving down the highway in heavy school traffic out of nowhere my car makes a clunk noise and all of these lights pop up on the dash. I roll the windows down and scream for my children to hold on because something was wrong. Luckily we were able to get to safety but I definitely had reduced breaking capabilities. I immediately take the car in and and find out my brake booster and accumulator has failed. Service tech brings up the consumer program but my car is a 2013 and it is not eligible to be repaired bc it’s 10+ yrs. Even though Toyota admits to internal malfunctions of the brake booster assembly, and my car is only at 76,000 mi it’s not being fixed. This is negligence on Toyotas part. Not fixing these faulty parts is endangering lives.

I have a 2014 Prius v with 92,000 miles. My anti-skid, brake and abs idiot lights went off approximately 1 week ago. (August 25, 2025) scheduled an appointment at my Toyota dealer (September 3, 2025) and was told there was an abnormal leak in the accumulator and that the brake booster pump and brake pump assembly needed to be replaced. Cost $5715. Not related to the brakes, but they also said I had to replace the rear shock absorbers as they are leaking and needed to be replaced and then realigned. Cost $1363. This should have been a recall not a mileage or 10 year limit.

I have a Prius v 2012, and the lights for abs turned on and when I checked on internet Toyota was repairing the part for 150k miles and 10 years but this is a safety feature my car is now at 149922, and while I was on road suddenly the signs came up and I the brakes were hard, and this is a problem for my safety and for others too since it doesn’t brake well.

See all problems of the 2012 Toyota Prius 🔎.

After 13 years and 112,000 the brake booster and brake booster pump went out on my car. Toyota extended the warranty to 10 years because of this issue. Now just outside of the 10 yr mark my car has this issue and Toyota will not cover it. This is a huge expense and also a major issue with this year and model of car.

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.

The abs, brake, tsc lights have all appeared on the dash. When running the obd codes, the error c1391 appears indicating a problem with the abs pump. When under the dash with the vehicle running, one can hear the abs pump engaging every few seconds which is not normal. After resetting the code. The error quickly pops back up. This is a known problem with this model Prius that Toyota is aware of. Toyota has not put out a safety recall for this issue. They refuse to make the repair of a faulty designed abs module, which is obviously a safety concern. The vehicle currently has 128000 miles with no other issues.

I was driving normally, about 30 mph in a residential area and the brakes all of sudden became soft. It was very scary and I didn’t know if it was safe to drive the vehicle. The brake, abs, and traction control sign all came on at the same time. I scanned the car and it was a c1391 error code. The Toyota dealership said it is not covered under any recalls. I called Toyota and asked about the zjb program that covered the repair but they said it expires. Toyota has a repair program for the defective part but no longer covers it. This issue is a known manufacturing issue and it’s dangerous. Toyota should cover it free of charge.

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.

Failed brake booster, pump, fluid, and actuator on my Toyota Prius 2013 with 143,972 miles on it.

The brake actuator failed, it can be available for inspection anytime. My abs light, brake light, and traction control lights all came on to indicate the failure. Since the hybrid engine requires the breaking system to recharge, failure of this part will eventually lead you to be stranded if it isn’t functional. Additionally, the responsiveness of the breaks makes driving at higher speeds a lot riskier. Toyota offered an "extended warranty" to have the parts replaced for free for 10 years or 150,000 miles, whichever came first. My make is 2014, at only 89,000 miles.

Brake booster, abs controller, and brake booster pump have failed for a second time. Parts replaced with new, in box from aftermarket dealer. Dealer/manufacturer refuses to accept that there are design flaws and will not recall.

When I’ve hit a pothole or hit the breaks to hard by abs, and traction control lights would come on and then turn off. The other day they all turned on and stayed on with the break light on as well. Breaks all seemed to work fine, just a little spongy. I brought it in to a shop and they estimated 3k to repair remove, replace, calibrate, and bleed abs accumulator assembly and brake master cylinder assembly. Test drive-new oem Toyota parts. These parts were recalled but only up to 10 years or 150k miles. I’m at 164k so ineligible for the recall but if this part completely failed while I was driving I could have been killed or caused someone serious harm.

Toyota issued a customer support program zjb for extended coverage of the brake booster and actuator assembly (this notice was not sent to the correct address the car was registered to with the dmv in 2019 so I never received the notice for this program) the Toyota program length was for 10 years or 150k miles. My car’s part just failed at 129k which is far below the 150k threshold. Despite being outside the 10 year window I am still under the mileage, the car is in perfect condition and this car is used for work for uber. The malfunction of the Toyota part in my car is a critical safety issue and because it is outside of the program Toyota refused to provide any goodwill assistance.

See all problems of the 2011 Toyota Prius 🔎.

I own a 2012 Toyota Prius c with approximately 156,578 miles. The vehicle has been diagnosed with c1391 – abnormal leak in accumulator, which causes the brake actuator to lose hydraulic pressure. This results in frequent buzzing from the actuator pump, illuminated warning lights (brake, abs, traction control), and loss of abs and stability control. The condition increases stopping distance and creates a serious safety hazard. Toyota previously acknowledged this exact defect under customer support program csp 21te01, which covered brake booster and pump assemblies for certain Prius and Prius c models when codes such as c1391 were present. However, the program expired on November 30, 2022, and my vehicle is just over the 150,000-mile coverage limit. Despite this, my Prius exhibits the same defect that Toyota has already recognized as a safety-related issue. Toyota carlsbad confirmed the diagnosis and quoted $3,399. 55 plus tax for repair, with a reduced courtesy estimate of $2,817. 86 plus tax, but declined goodwill assistance since csp 21te01 expired. Given the widespread reports of brake actuator failures in Prius models, I believe this represents a systemic safety issue that warrants NHTSA investigation and potential recall/extended coverage.

Abs failed and mechanic tells me my actuator needs replacement which is a known issue with my generation of Prius.

See all problems of the 2008 Toyota Prius 🔎.

The hybrid braking systems on Toyota Prius' manufactured from 2010-2015 had a serious failure of the hybrid braking system that had additional long term warranties to repair, but never recalled in order to save the money from a total recall. The sloan Toyota dealership in glenside knew before I purchased the 2013 Toyota Prius I purchased that a serious brake system failure was very probable with my car but failed to tell me. If they did, I would not have purchased the car. I had the 5000 mile oil change in early August and three days later after the service and a clear 25 point inspection, and the system failed. I want full reimbursement or just pay for the repair.

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.

While driving on the highway, all the brake-related warning lights appeared on the dashboard. This was accompanied by a frequent electric buzzing noise (every 15-20 seconds, lasting two seconds each time). The brakes became difficult to press, almost spongy, and required more pressure to function. Upon taking it to the dealer, I was told that the vehicle (a 2013 Prius v with 181k miles) needed a new abs pump and brake actuator, totaling roughly $4100.

Have multiple warning lamps that light up on and off and the brakes in my car get spongy making the braking unsafe. The lights that turn on are the steering/ traction , brake, and abs light. There are multiple complaints online on youtube from similar issues ongoing and no recall made. My mechanic says it indicates a leak however there is no brake fluid missing and on youtube there’s work arounds because people keep getting the same message, yet no recall has been made. This can affect steering and cause an accident. Please recall soon. Including youtube link so you can see all the comments and issues from thousands that don’t know how to report but view to fix temporarily. [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Apparently Toyota knows of a recurring problem with the brake actuator. I took my Toyota Prius to the dealer for an unrelated recall issue that they repaired and I asked them what the sound was that I kept hearing every 10 seconds or so. The told me it is the brake actuator, but did not seem concerned at all that I get it repaired right away. They did quote me a very high price to have it fixed by them. I have chosen to take it to my mechanic for repair. In the mean time, I decided to research this on the internet and discovered that it is a known problem by Toyota and there is a class action suite filed on them. I want Toyota to pay to have it fixed! I fear for my life and lives of others with the same issue.

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.

Toyota has a break issue that they extended the warranty for 10 years or 150000 miles and now a few months pass the 10 years I have a problem with the actuator giving warnings and my daughter went into a skid when applying the breaks. She was lucky and didn’t hit anyone. If Toyota knows there is a problem that is a safety concern they should fix it I did get a Toyota dealership to give an estimate to fix it and was told $4300. 00 I think that’s too much for a defective part. It should be a safety recall.

Brakes have failed with a dtc c1391 indicating an accumulator leak. The brake booster pump constantly runs. When the dtc is triggered the brake feel becomes suddenly different as regen braking is lost. Appears to be a very common and expensive repair. Toyota has already had recalls and extended repair program for these parts but they are now expired and not covered.

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

I am experiencing the issue described in the brake booster and brake booster pump assemblies recall issued by Toyota for the Prius, which for me ended in 2023. The vehicle is unsafe to drive without performing this $4000 repair (dealer cost), which is almost more than my car is worth. Toyota should issue another extension for the repair coverage since they are known to be faulty. The previous recall and extension of the recall can be found here: [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The abs system and the brake actuator began to fail, which triggered multiple warning lights. The Toyota dealership service department confirmed that the anti-lock brake system and the actuator needed to be replaced, a $3800 value.