2010 Toyota Prius brake problems

SERVICE BRAKES

ABS light came on 6 months ago as well as ((!)) light. As soon as those lights came on, the brakes had an increased stopping distance and it became harder to get the car to come to a complete stop. I have seen a few Prius owners in my area also having the same problem with their Prius. For my car, the ABS light would come on, then turn off for 300 or so miles, then turn back on and stay on for about 300 miles. That has lasted for 6 months. I had almost gotten in an accident yesterday after getting brake lines fixed for 4th time, and we determine the actuator and accumulator are both bad. I have also seen a lot of Prius owners with the same code. Where I am at, my shop is quoting me $2300 for the fix in total. That is absurd.

NHTSA complaint #11742107 — an unverified report by a vehicle owner.

SERVICE BRAKES

My 2010 Prius has experienced the following error codes: C12341 and C1391, prompting the dealer to recommend replacing the brake booster assembly and master cylinder for $3938.89. This is a known issue with this vehicle and a Customer Support Program (CSP) was issued back in 2018, stating that if this vehicle displayed these codes, the repairs would be at no charge to the customer. Toyota extended this coverage to 10 years from date of first use or 150,000 miles (whichever came first). I never receied the notice. The details of the CSP are below. (I found on the internet.) "Toyota has received reports indicating various brake system related warning lamps illuminate due to internal malfunctions. The Brake Booster and Brake Booster Pump are covered by Toyota’s New Vehicle Limited Warranty for 3 years or 36,000 miles (whichever occurs first). However, because we at Toyota care about each customer’s ownership experience, Toyota is now offering a voluntary Customer Support Program that applies to various brake system related warning lamps of covered vehicles as a result of internal malfunctions, regardless of whether the vehicle is out of warranty. The timing of any repair under this voluntary Customer Support Program is subject to parts availability. The Customer Support Program will be offered for all vehicles until November 30, 2019, regardless of mileage. In addition, the Customer Support Program will be available for 10 years from the date of first use, or 150,000 miles whichever occurs first." My vehicle has about 132,000 miles and just displayed theses codes. Since it is 16 years old, the CSP has expired. It being a known issue, and one related to such a safety concern, I emplore you to make this a formal recall rather than a mere suggestion of repair. Back in 2018, my vehicle was not displaying these codes so was ineligible for the repair. Upon further research I am finding hundreds of Prius owners with the same issue. Clearly this is a defect in manufacturing.

NHTSA complaint #11732957 — an unverified report by a vehicle owner.

SERVICE BRAKES

There are issues with the brake. Many times the brake pedal goes down to the floor and it losses ability to stop. Apparently there is a common ABS actuator and Brake issues. Toyota will not address the issue

NHTSA complaint #11727774 — an unverified report by a vehicle owner.

SERVICE BRAKES

i have have 2 problems, both was recalls, but this one they say expired in 2021 when i bought the car and toyota dealer didnt tell me had recall so i could fix it before it expired. there is a class action lawsuit in the brake booster, master cyclinder actuator abs pump fialing loosing brakes making grrr noises leaking all brake fluid out continously dangerous to drive can cause bad accident wreck since i drive down the hwy alot and this is the only car i have to drive, i also have dc inverter module /sensor that is killing off 3 batteries now that i installed in 3 months, and toyota dealers wont fix unless it shows error but its a recall so since problen should fix this recall but wont pay for it to fix it even though it a recall right now that is not expired. im upset 3 dealers wont do it unless then charge me to do it. when toyotal mfg take it to any dealer and they will fix free but no one will do it. toyota mfg needs to make these dealers fix these 2 recalls on this car that can kill me and my passengers and anyone on the road that i could hit by not haivng controll brakes or the hybrid system shuttong completely down and could even kill a pedestrian with these 2 recalls that dealers wont fix but mfg said they need to everyone with these cars i see are having these same problems. need make the toyota mfg and dealers fix these free of charge before more people get killed injuried or cause more accidents ,

NHTSA complaint #11723750 — an unverified report by a vehicle owner.

SERVICE BRAKES

While driving my 2010 Toyota Prius, the brake warning lights suddenly illuminated and the brake pedal became soft and unresponsive. Stopping distance increased significantly, and the vehicle required much more pressure to slow down. This created an unsafe situation in traffic and could have easily resulted in a collision. A Toyota dealership diagnosed the issue as a failure of the brake booster and brake booster pump assembly (DTC C1391). This is the same failure Toyota previously acknowledged in Customer Support Program ZJB for 2010–2015 Prius models. My vehicle is experiencing the exact symptoms described in that program, but the support period has expired even though the mileage is well within normal expectations for a hybrid of this age. The sudden loss of braking assist is a serious safety hazard. There was no warning before the failure, and the vehicle became difficult to stop immediately. This appears to be part of a widespread pattern of brake booster failures on this generation of Prius, and the defect poses a risk of crash or injury. I am filing this complaint because this is a safety‑critical component that should not fail under normal use, and many other owners have reported the same issue. A review or investigation may be warranted given the frequency and severity of these failures.

NHTSA complaint #11722046 — an unverified report by a vehicle owner.

SERVICE BRAKES

In 2019 Toyota repaired my 2010 Prius(120,189 miles) braking system under the ZJB program. The brake cylinder assembly and brake booster pump assembly were replaced as they had a known defect that caused the braking system to fail. As of February 27, 2026 the replaced components are failing again. The auto has approximately 224,000 miles. So the replacement components failed in less miles and time then the original equipment failed which was determined to be faulty. Toyota has declined any assistance in the matter.

NHTSA complaint #11721184 — an unverified report by a vehicle owner.

SERVICE BRAKES

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 affected component remains available for inspection. Following the incident, an authorized Toyota dealership inspected the vehicle and reproduced and confirmed the condition. Service records indicate the brake booster pump assembly had previously been replaced under a Toyota safety recall. Despite this prior recall repair, the same component failed again after approximately 41,000 miles of service, demonstrating that the recall remedy was ineffective. As a result of this failure, the vehicle was rendered unsafe to operate. Despite dealer confirmation that the malfunction involved a previously recalled safety component, corrective repairs were declined, with warranty limitations cited rather than addressing the repeat safety-related failure.

NHTSA complaint #11707945 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11705550 — an unverified report by a vehicle owner.

SERVICE BRAKES, HYDRAULIC

The contact owns a 2010 Toyota Prius. The contact stated that while driving 70 MPH, the vehicle jerked, and the vehicle failed to accelerate as intended while depressing the accelerator pedal. Additionally, the steering wheel seized, and the vehicle stalled. The contact pulled over to the side of the road, opened the hood, and disconnected and reconnected the battery terminals to reboot the vehicle. The contact stated that a yellow triangle warning light and the check engine warning light were illuminated. The message "Check Hybrid System" was displayed. The contact was able to restart the vehicle; however, the vehicle failed to exceed 65 MPH while driving. The ABS warning light was illuminated. The contact took the vehicle to Auto Zone and O'Reilly's; however, no cause for the failure was found. The vehicle was then taken to the dealer. The contact was informed that the failure might be an ABS system failure. The vehicle was not repaired due to the cost. The contact stated that the failure first occurred years ago, and the failure persisted. The manufacturer was not notified of the failure. The failure mileage was unknown.

NHTSA complaint #11702535 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11697157 — an unverified report by a vehicle owner.

SERVICE BRAKES, HYDRAULIC

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.

NHTSA complaint #11697157 — an unverified report by a vehicle owner.

SERVICE BRAKES

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 back to the break actuator being faulty which is very expensive to even repair for something that is obviously a poor design.

NHTSA complaint #11691291 — an unverified report by a vehicle owner.

SERVICE BRAKES

The brake and pre collision system suddenly fail without warning.

NHTSA complaint #11690902 — an unverified report by a vehicle owner.

SERVICE BRAKES

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)

NHTSA complaint #11685121 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11684476 — an unverified report by a vehicle owner.

SERVICE BRAKES

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 hour. You press the brake to start slowing down, and while decelerating, the dashboard lights up and the brake pedal goes spongey. Now, you must slam the brake all the way into the firewall to engage the disks and pads exclusively. Aside from the imminent terror of hitting the car in front of you, now you are skidding on the brakes, worried the car behind you will crush the rear. Sooner or later this will cause somebody to get into an accident when a split-second decision cannot to be made quickly enough. The issue is well-known, and a warranty recall was issued, but it does not cover any vehicles over a certain age and mileage. It has been reproduced by my local mechanic and inspected by a Prius specialist, who both quote about $3800 to fully replace and recalibrate the failing parts. There were no indicators of this issue before it happened to my wife and I the first time on the highway. While I am grateful that nobody was injured, the situation could be completely different had the problem occurred just seconds later.

NHTSA complaint #11683582 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11679218 — an unverified report by a vehicle owner.

SERVICE BRAKES

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 the previous campaign, whether they were experiencing a failure or not, during that time period since Toyota knew that these parts are faulty.

NHTSA complaint #11672181 — an unverified report by a vehicle owner.

SERVICE BRAKES

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

NHTSA complaint #11671942 — an unverified report by a vehicle owner.

SERVICE BRAKES, HYDRAULIC:ANTILOCK/TRACTION CONTROL/ELECTRONIC LIMITED SLIP:ABS WARNING LIGHT

The contact owns a 2010 Toyota Prius. The contact stated while driving 45-50 MPH and depressing the brake pedal, the ABS, the traction control, and the check engine warning lights were illuminated. The contact stated that the vehicle experienced reduced braking power and the vehicle failed to respond as needed. The contact stated that upon engaging the brake, the vehicle decelerated, and the contact pulled to the base of an inclined side street, where the vehicle was able to stop. The contact was able to safety park and inspected the vehicle. The contact was able to drive to the residence at slow speeds. The vehicle was taken to the dealer, where it was diagnosed that the brake booster and master cylinder had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 94,000.

NHTSA complaint #11670352 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11666573 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11666335 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11660987 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11660115 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11659119 — an unverified report by a vehicle owner.

SERVICE BRAKES

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 be held responsible and honor/extend any and all recalls. Again, I'm waiting to hear back from them, but was advised by many other Prius owners to file a complaint with NHTSA.

NHTSA complaint #11658300 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11655931 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11652694 — an unverified report by a vehicle owner.

SERVICE BRAKES

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.

NHTSA complaint #11652185 — an unverified report by a vehicle owner.