2010 TOYOTA PRIUS Service Brakes Problems

On November 25, 2025, at approximately 11:45 p.m., our 2010 Toyota Prius experienced a braking system malfunction during normal operation. The brake pedal required significantly increased effort and the vehicle exhibited reduced braking performance, indicating a loss of brake power assist. The vehicle required increased stopping distance, creating an immediate risk of a collision. At the time of the failure, multiple warning indicators illuminated simultaneously, including the brake system warning, ABS warning, check engine light, battery warning, steering warning, tire pressure warning, and vehicle stability control/slip indicator. There were no warning lamps or abnormal symptoms prior to the failure. The failure was determined to involve the brake booster pump assembly, a component responsible for maintaining hydraulic brake assist pressure. This component is known to experience internal accumulator housing degradation, which can allow nitrogen gas migration into the brake fluid and result in partial or complete loss of brake assist. The...

Car keeps throwing a C1391 Abnormal Leak in Accumulator code. The ABS, traction control, and brake lights are all illuminated. Hissing sound from brake pedal. Spongy feel when braking and incredibly soft braking as well, very hazardous to driving and stopping. This is a known issue with the 2010-2015 Prius, and a quick internet search shows thousands of other Prius owners who also have this issue with their vehicles. It’s a safety hazard and can be potentially life threatening. Toyota is not doing anything to rectify this potentially fatal issue that impacts thousands of vehicles and vehicle owners and their families. Estimated cost of repair is upwards of $4,000 and simply not affordable to most consumers. Actions needs to be taken IMMEDIATELY by Toyota to recall these vehicles and fix them.

The contact owns 2010 Toyota Prius. The contact stated that while depressing the brake pedal, the ABS, brakes, and the vehicle stability control warning lights were illuminated. An Independent mechanic was contacted. The vehicle was taken to an independent mechanic where it was diagnosed and determined that the brake booster and accumulator needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and informed the contact that the VIN was not included in the recall; however, the recall had expired. The failure mileage was 172,000.

One day after arriving home from work, all the sudden my ABS light, BRAKE light and traction control light turned on, my brake pedal being harder to push, and my car making weird humming noises every 5 seconds. Upon taking my 2010 Prius to my trusted repair shop, it was revealed that my break actuator was faulty. I drive on roads that need this part to WORK! Especially in the height of construction going on PA. One of the roads that I take has been milled up and upon driving on that road I nearly swerved onto the side walk 3 times! My breaking has been harsh and with one incident that nearly didn't break in time at all! Doing research and looking into the active investigations on this part, it turns out I am one of possible thousands who are dealing with this issue that has all been tied...

The brake and pre collision system suddenly fail without warning.

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)

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.

It is a known problem that Priuses manufactured from 2004 to 2015 have issues with the brake master cylinder and brake booster accumulator. When the vehicle computer recognizes an internal leak (ABS C1391) or other issue in the accumulator pump, it completely disables the regenerative braking system, which significantly reduces braking power. In my case, the problem is intermittent, and the vehicle computer will occasionally clear the code and operate normally. A slight whirring sound can still be heard (indicative of an internal leak), leading me to conclude that the part is still damaged, even when the code clears itself. This continues to affect my and my passengers' safety because the problem comes back with no warning while driving. Many times at highway speeds, the regenerative braking system will shut off while decelerating. This has caused scares and near-accidents. Imagine you are approaching stopped traffic while traveling 65 miles per...

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.

A few weeks ago, while waiting at a traffic light, the brake warning lights (ABS, Emergency brake, Traction control) lights on my 2013 Prius lit up and the brake pedal suddenly becomes much less responsive. I drove carefully back home, and researched online what the problem could be. To my surprise, this seems to be a known problem to Toyota, who had issued a campaign in the past to address this problem (ABS actuator, pump) and to replace the known faulty parts for free, but only for owners who were experiencing a failure at that time. Now the recall has expired, and owners like me who weren't having a problem at the time are stuck in a situation with cars that have a known, dangerous fault, while Toyota refuses to help with the problem anymore. The approximate cost for replace/repair is over $4000. All owners should have been included in...

What component or system failed or malfunctioned, and is it available for inspection upon request? Brake Actuator failed requiring replacement of booster assembly with master cylinder and booster pump assembly How was your safety or the safety of others put at risk? This greatly impacted braking and stopping distance Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, Toyota Dealership Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, Toyota Dealership Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No. These lights appeared after the failure - Brake, ABS, Traction Control

While driving on the freeway the Traction control light, ABS light, Brake System Light and Brake light all came on. Fortunately I haven't had any issues but when I took it to the a dealership I was told that the Brake booster and pump need to be replaced as the master cylinder was leaking into the brake fluid and given an estimate of $3500 for the repair. People online have said that after having this issue the brakes can go out at any time. I am unable to pay for the repairs at the moment so I have to drive with the knowledge of having my brakes going out at any time.

Toyota issued a recall with a limited time for Prius brake booster/actuator failures. This issue is known to present brake failures and necessarily place drivers, passengers, and pedestrians at risk in the case of such brake failures. Toyota made no effort to proactively remedy this problem and further neglected customer safety by excluding Priuses with the same manufacturing issue from the recall, under its 10 year 150,000 mile requirement. Whether or not the Priuses have been driven 150,000 miles or 10 years the nature with which the malfunction presents represents a safety for any driver.

C1391 error, "Abnormal Leak of ACC PRESS". This is a common failure in many prius and requires the replacement of the brake master cylinder and brake accumulator. Toyota has an expired customer support program but no actual recall. Parts were replaced to bring braking system back into working condition.

I purchased a used 2010 Prius on May 1, 2025. On May 5, the car would not turn on. Thought it was the battery. Replaced the battery on May 6. On May 8, the battery was dead again. I jumped the car and tried driving it to the Toyota dealership to have it looked at. On the way a loud beeping sound started and the ABS light came on. I pulled over and noticed the brakes felt strange. After having it towed to Ourisman Toyota, the told me the brake booster was broken causing the battery to drain. The cost for repair is a little over $4,000. This almost half of what I paid for the vehicle.

Code diagnostic C1391 ABS system. I have replaced this in my previous 2009 Toyota Prius, it has been replaced in this 2010 Toyota Prius, and now needs to be replaced AGAIN in the 2010 Toyota Prius. It’s incredibly dangerous, no warning signs, spongy brakes all of the sudden that barely feel like they’re going to work. It puts not only myself in danger, but others especially when it just happens without warning and all of the lights come on as you are driving and the brakes become extremely wonky.

We have a 2010 Toyota Prius. All the sudden we got errors/warnings on our dash about ABS and traction lights, and brake light, staying on all the time. Brakes extremely sluggish, and from doing research advised not to drive it. Toyota did a diagnostic test which came up as C1391, bad ABS booster pump and master cylinder. This is a huge safety issue, others have reported brakes completely going out on the highway, and also reporting Toyota is not paying for fixing the issue, and only "certain Priuses" meet their criteria to pay for repairs. There supposedly was a recall at some point but we NEVER received it. I have contacted Toyota America and waiting to hear back. It is going to be very expensive to repair, about $3500-$4500. Yes, it is a 2010, but from what I'm reading and hearing is a MAJOR safety issue and Toyota needs to...

My brake booster master cylinder and pump assembly went out while driving on the freeway. My brakes became soft and unresponsive, though I was able to exit the freeway without incident. My ABS light, brake light, and traction control lights all came on. The lights have since remained on and my brakes continue to malfunction. My local repair show diagnoses the issue with the diagnostic trouble code: C1391 Back in 2018, before I owned the car, Toyota offered an "extended warranty" to have the parts replaced for free for 10 years or 150,000 miles, whichever came first. I'm past the year threshold but well short of the mileage one. I feel a recall should be made and the repair covered, as this is clearly a safety issue.

My ABS system light is on. The Toyota mechanic has determined that it is due to Nitrogen gas from a component of the brake booster pump assembly could leak into the brake fluid. As nitrogen is released into the brake fluid, the brake pedal may have reduced hydraulic pressure. Under certain circumstances, this condition could affect stopping distance and increase the risk of a crash. Toyota recalled model year 2010 Prius vehicles manufactured March 31, 2009, through October 9, 2009. I took my Prius to Toyota to fix this ABS recall problems but they are refusing to fix the problem for free. They are charging me $4000 to fix it.

ABS, traction, and brake warning lights came on. No OBD code reading. Mechanic says needs brake booster pump; brake booster master cylinder. Theoretically mine were serviced but no way for me to actually verify it happened on the recall. Vehicle located in Kamuela, Hawaii.

- Brake system failure - Safety risk due to longer stopping distance - Problem was reproduced and confirmed by two repair shops - Components were inspected by repair shop - Several brake warning lights were ON on dashboard AFTER failure occurred. Toyota recalled 2010 Prius vehicles for Brake Booster and Brake Booster Pump assembly failures. Recall code D0H. Toyota claims that the replacement parts are fixed for the gasket leak issue. Toyota replaced these parts on my car in 2013 as part of the recall. The replaced parts labeling are verified to be the claimed fixed ones. But only about 62,000 miles after the D0H repairs (odometer at 81,400 miles) the parts failed again on March 20, 2015. I do not put many miles on my cars. Toyota has put a maximum repair date for this issue knowing failures keep re-occurring (No repairs supported after 2019). Toyota has not fixed...

I am writing to express my concern regarding an issue with the PCS System dash lights on my 2010 Toyota Prius. I recently became aware of problems related to the brake booster system, which I understand have been addressed through recalls or warranty extensions on certain models. I believe that the issue I am experiencing should be covered under warranty, and I kindly request your assistance in resolving this matter.

I drove the car to my destination without any issues. An hour later, when I restarted the vehicle to leave, the following dashboard lights were on (slip indicator, ABS warning light, and brake system warning light). When I drove the vehicle, the brakes had diminished stopping power. It took farther for the vehicle to come to a full stop when applying the brakes. When we had it checked by the Toyota dealer we were informed that there was an abnormal leak in the accumulator assembly (system diagnostic code C1391) and it would need brake booster/master cylinder assembly with accumulator pump replacement.

Brake booster, brake accuater went out even after the recall. Dealership said they could do nothing to help

While driving at a high speed in the left lane of a 2 lane interstate a car in the right lane merged into me. Luckily I was able to brake in time to avoid a collision, unfortunately the sudden braking at a high speed caused my car to loose all control. Upon braking my front tires lost all traction and shifted my car to the right, I remained horizontal sliding across the highway for an unrecognized distance (my guess is 10-20 meters), before shifting another 90 degrees to the right leaving me backwards. At this point I had shifted across both lanes and the emergency lane, I was backwards in a grass border on the right side of the interstate. If this had been any other sort of barrier I may not have Lived. This incident has not been reproduced or confirmed by a dealer or independent service center. The...

Dear NHTSA Team, I am filing a safety complaint regarding my 2010 Toyota Prius (VIN: [XXX] ) due to ongoing brake system failures. My vehicle is affected by Safety Recall D0H (Brake Booster Pump Assembly – Accumulator), but Toyota refuses to replace all necessary components for a proper repair. Issue Summary: •My brakes have intermittently failed, requiring excessive pedal pressure and causing delayed stopping, putting me at serious risk. •I took my car to Toyota on Edens for the recall repair, where Service Advisor David confirmed that the brake booster and accumulator should be replaced together. •However, Toyota will only cover the accumulator under Recall D0H, despite the brake booster being critical for safety. •My vehicle has Diagnostic Trouble Code (DTC) C1391, indicating an internal leak in the braking system, but Toyota refuses to cover the booster replacement. Toyota’s Response: •I contacted Jessica from Toyota’s Customer Experience Center (Case Number:...

Abs lights on, traction light on .Actuator running cicle constantly . Breaks felt spongy

Break booster fail. Will cause the breaks to fail. There was a voluntary recall on these but I never recieveed the letter in the mail. Thr break booster failed after the voluntary recall was up. Toyota said they cannot help with this. Other prius owners i talked to have the same issue with their 2010 prius break boosters and also did not get the letter in the mail.

ABS Pump/Motor failed. Lost power and control over the breaks . ABS light on

My car, a 2010 Toyota Prius, Level V has about 161,000 miles on it, and I have driven about 140K of those miles over the last 13 years. I have traveled around the DC/Maryland area and also taken the car on long trips. The car has been reliable, safe, and predictable... EXCEPT in one place/instance. I have probably driven a dozen times or more to the BWI airport from my home in Chevy Chase. On the return drive on [XXX], as I drive towards an overpass that is just before the [XXX] exit, my Prius goes into "Emergency Approaching Collision" mode. The brakes automatically forcibly apply, the seatbelt/lap harness grab me, and there is an emergency beeping from the system. The first time this happened... probably 10 years ago, it was very startling. My car was traveling about 60-65 mph. Luckily, there were no cars behind me... and I remained...

Twice while I was driving on the highway, my ABS and brake light came on, and my brakes became less sensitive to pressure. That is to say, it took more effort and I had to push my brakes further towards the floor in order for them to respond. I went to an independent mechanic and got the code C1391 which indicates a brake pump accumulator issue. I went to a Toyota dealership and and had the car inspected. They confirmed the C1391 code and said the brake booster assy with master cylinder pump assy was malfunctioning. However, I was never told by Toyota that this issue meant my brakes could fail at any time. My safety and the safety of others was put at risk because my brakes spontaneously became less responsive, my stopping distance was increased, and they were at risk of spontaneous failure.

I was coming to an intersection where two cars were waiting for a right turn. I pressed on the brakes and nothing happened. The car continued to move without slowing down. The brakes felt "blocked" and unresponsive. I engaged the manual break at the last moment and that slowed me down. But I still hit the car in front of me which in turn hit another car in front of it. The police report says "following too close". But I was not following other cars. The two cars were already at the intersection. I was just coming to this intersection and attempted to slow down as usual. Except that the brakes did not respond. My car was a total loss.

I recently had an issue with the brake actuator on my 2010 Toyota Prius, showing error code C1391. This caused reduced braking efficiency, and research shows it’s a common safety concern with Priuses. While there was a recall, it has expired, leaving owners like me without support. I kindly request an investigation to address this critical issue for the safety of all affected drivers.

Please read the attached file "prius complaint signed" for a full description. I am the owner of a 2010 Toyota Prius, 2ZR-FXE. The warning light came up on my dashboard of my vehicle, so I took my 2010 prius to AutoZone, to get a free diagnostic. The diagnostic indicated the problem code of “C1256” “Accumulator Low Pressure” for the “Anti-Lock Brake System.” See Ex. A (AutoZone Diagnostic). It is available for inspection. According to the safety recall number “D0H”, 2010 prius model “2ZR-FXE” has a “Brake Booster Pump Assembly which can develop a crack inside the accumulator housing. If this occurs nitrogen gas could leak into the brake fluid and gradually cause a loss of power assist. Under certain circumstances, THIS COULD AFFECT STOPPING DISTANCE AND INCREASE THE RISK OF A CRASH.” (Emphasis added). I have noticed that when I brake hard, IT TAKES LONGER TO COME TO A STOP,...

My brakes stopped braking but luckily I could drive slowly into a curb in my neighborhood. God knows what could’ve happened if I was on the freeway. All the dash lights came on at the same time so I ran some codes; it came back C1391 - the brake actuator is broken. Toyota will not cover it despite this being a very common issue. My car is undriveable until this gets fixed because it will not break.

The contact owns a 2010 Toyota Prius. The contact stated while driving approximately 40 MPH and depressing the brake pedal, the brake pedal was stiff and required excessive force to depress. The contact stated that the ABS, Stabili-trac, and Parking Brake warning light was illuminated. Additionally, the contact stated that a chime sounded and could not be turned off. The contact stated that the failure had been intermittent but was a recurring failure. The contact had not taken the vehicle to a local dealer or independent mechanic. The vehicle was not diagnosed or repaired. The contact researched online and related the failure to NHTSA Campaign Number: 13V235000 (Service Brakes). The manufacturer was not informed of the failure. The failure mileage was approximately 77,000.

hope this message finds you well. I am reaching out regarding a potential recall issue with my 2010 Toyota Prius. The vehicle's VIN is [XXX] , and I am currently located in the Austin area. Recently, my vehicle has been experiencing problems related to the brake system, specifically the brake booster pump assembly. The diagnostic results returned codes C1241, C1391, and C2300, which point to issues such as abnormal leaks in the accumulator pressure and actuator system malfunctions. Given that this issue may fall under a recall or extended warranty for the brake booster pump assembly, I would appreciate it if you could confirm whether my vehicle qualifies for this service. If it does, I would like to schedule an appointment to bring my car into the nearest authorized service center to have the necessary parts replaced. Please let me know if any additional information is needed. I look forward...

Toyota failure to honor recall. See correspondence below for NHTSA ID and other detail. NTHSA Recall ID: 13V235000 Toyota Case#: [XXX] Very dissatisfied with Mr. Lxxxx's denial of our inclusion in the customer support program. He seemed to reach for every imaginable escape hatch to say "no". Claiming 2 notices were sent out (to the correct address) between December 2017 and March 2018, neither of which reached me, is dubious to say the least. The likelihood of our remaining a Toyota "family" with the eventual replacement of our 3 vehicles (including a previously unmentioned 2017 Rav4) has shrunk considerably. Shame on Toyota North America. ---------------------------------------------------------- (earlier Monday, October 21, 2024 at 11:31:54 PM EDT) Dear Mr. Oxxxxx: I’m writing to express my distress at being disqualified for this expensive safety recall about which I was never notified by mail and, despite receiving maintenance and inspections at the dealership in slim...

In August of 2024, my 2010 Prius with less than 100,000 miles - all the brake warning lights on the dash suddenly came on - without any prior warning. The brakes felt a little "funny" at the time, so I took it to my mechanic immediately because my safety or the safety of other was at risk if the brakes completely failed. My mechanic informed me that there was a TSB for the brake booster with master cylinder and brake booster pumps that Toyota new about. I felt that it was imperative that this was repaired immediately. Apparently Toyota knew about this issue but did not notify me in any way at any time. I bought this Prius new and have had regular service check ups. I had to pay nearly $5,000.00 to have this repaired which I feel that Toyota should reimburse me, and any others who had this...

ABS and brake lights lit at around 141000 miles code C1391 came up during diagnosis.

Brakes started making a hissing sound a couple of weeks ago. Yesterday evening when I was driving on freeway , I got an assortment of lights on my dash while driving . ABS was instantly disabled and it was significantly harder to brake the car. BRAKE light on dashboard came on. Traction control light came on . It was very dangerous and it was mere luck that there was no car in the front - otherwise I could have crashed. Pulled over to the side on the freeway and then came in internal roads to my destination , keeping a lot of braking distance and at slow speed. Turns out this is the infamous brake booster leak that was so bad Toyota was forced to create an extended warranty program on Gen 3 to fix it. Brought it to dealer next day. Got an estimate for $4000 for "REPLACE BRAKE...

The contact owns a 2010 Toyota Prius. The contact stated that while driving at various speeds and the brake pedal depressed, the vehicle lunged forward. On a most recent occasion, the contact was attempting to park the vehicle and after shifting into the park position, the vehicle lunged forward as the brake pedal was depressed causing a minor collision with a curb and another vehicle. The contact mentioned the brake pedal required excessive force in order to come to a stop and that there was an abnormal noise present. The contact was concerned that the failure would progress causing a severe accident. A police report was not filed and there were no injuries sustained. The vehicle was taken to an independent mechanic where it was diagnosed that the ABS System failed and advised the vehicle be taken to a dealer. The vehicle was not repaired. A dealer was not contacted....

Heading westbound on I-70, taking Exit 29 off ramp from highway, I drove over uneven pavement. My traction control, ABS and brake lights illuminated, the brakes suddenly felt mushy. As I approached the stoplight at the end of the exit ramp, I questioned whether I would be able to stop. Scared me immensely. Luckily no cars were near me. I now do not have ABS, Traction Control, stability control OR regenerative braking.

Toyota refuses to cover a recall that I was never made aware of. My Prius need to have ABS Brake Accumulator and other components replaced. My VIN I was told had a recall but I was never made aware. I was told it may not be safe to drive my car. Toyota told me I would have to cover all cost for the repair and for my family that is just not possible. For the safety of my family, I am hoping NHTSA can help me in anyway.

NHTSA CAMPAIGN ID: 13V235000 Toyota will notify owners, and dealers will replace the affected brake booster pump assemblies. The recall is expected to begin late July 2013. Owners may contact Toyota at 1-800-331-4331. Toyota is no longer honoring this recall. They think it is acceptable for me to drive around with unsafe and defective brakes.

In 2015 I purchased my Toyota Prius in VA. I now live in Indiana and had my car checked for a possible sensor issue because the traction, brake & abs light were coming on and off. The diagnostic showed a brake accumulator leak malfunction. I contacted Toyota dealership once I was told there was a recall. The dealership said that it was showing it was replaced in 2013 from the previous owner in VA. It was listed then as a recall. I contacted Toyota Corporate and they said that it went from a recall to customer support with a maximum of 150,000 miles. I did not have any more problems until just recent. My argument is once a recall it should still be repaired. The part appears to be the problem. It is a safety issue and I need Toyota to fix the problem. Thank you!

The car suddenly threw a C1391 code yesterday with no previous warning. The traction, parking brake, brake system, and ABS lights are all lit on the dashboard. As this vehicle is my daily commuting vehicle, I must have the costly repairs performed, which are estimated at roughly $2,400. I will ask to retain the parts for inspection. The brakes are softer, and the breaking distance required has increased by approximately fifteen feet.

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....

The contact owns a 2010 Toyota Prius. The contact stated while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. In addition, the contact stated that several unknown warning lights were illuminated. The vehicle was taken to an independent mechanic where it was diagnosed with brake system failure. The contact was informed that the braking system needed to be replaced. The vehicle was not repaired. The contact was advised to take the vehicle to the dealer for service. The contact was made aware of Customer Satisfaction Program: C1391. The vehicle was taken to the dealer where the vehicle was diagnosed with brake system failure. The contact was informed that the braking system needed to be replaced. The contact was informed that the repair was not covered under the Customer Satisfaction Program: C1391, because the mileage had been exceeded. The manufacturer was...

ABS Lights turned on and need replacement. This is my 3rd Prius that have the Issue.