2014 Toyota Prius Owner Complaints

I am submitting this complaint regarding a serious safety concern involving the brake actuator/booster assembly on my 2014 Toyota Prius. My vehicle has experienced failure of this critical braking component and has been unable to be properly repaired since November due to difficulty obtaining the correct replacement parts. This involves a major safety system required for proper braking operation. Brake actuator/booster assembly. Diagnostic codes: B1206, B2321, C1252, C1253 C1256. Toyota previously acknowledged brake actuator concerns through Customer Support Program ZJB. However, my vehicle is outside the program limits despite experiencing what appears to be the same type of failure reported by many other Prius owners. Since November, I have faced difficulty obtaining the correct parts, reports of nationwide backorders or limited availability, conflicting information regarding updated Toyota part numbers, and concerns about repair providers advertising new OEM parts that may actually be aftermarket or incorrect components. This creates a safety concern because owners experiencing brake failures may be unable to obtain timely repairs using verified, appropriate parts. Repair estimates have ranged from approximately $3,000 to over $4,000, including a Toyota dealership estimate of approximately $4,100. This creates a significant barrier to restoring a vehicle to safe operation, especially involving a component Toyota has previously addressed through a customer support program. I request that NHTSA review this complaint and similar reports to determine whether further investigation is warranted regarding Toyota Prius brake actuator failures, parts availability issues, and whether additional manufacturer action or support is needed. A vehicle’s braking system is a fundamental safety component. Owners should be able to obtain a safe and reliable repair without months of delay or uncertainty regarding replacement parts.

NHTSA ID

11754349

Incident

Nov 11, 2025

My car experienced a failing brake actuator/accumulator. The first sign was the ABS and break lights accompanied by a whoosing sound. The issue causes intermittent system wide break failure and renders the car undriveable. Toyota had an extended warranty for this issue but that offer was closed by the time my car had the failure even though it was still under 150,000 miles. I believe this is a significant safety issue and should rise to the level of a recall by Toyota.

NHTSA ID

11751206

Incident

May 16, 2026

Brake actuator had been making noises and it finally stopped working on 7/14/26. Thankfully my car was and stopped and parked. The car has 137k miles on it, one owner and no explanation of what caused this. There were no accidents, abuse, or failure to maintenance.

NHTSA ID

11750234

Incident

Jul 14, 2026

The traction control, abs, and emergency brake light came on. We checked and the code produced was C1391. There’s a humming noise every 10 or so seconds when idle. The humming noise is also present when braking. We did some research and this appears to be an issue with Toyota Prius. We called the dealership and were informed that this was not a known issue. Thank you.

NHTSA ID

11748069

Incident

Jun 30, 2026

Car is at less than 105k miles and yet brake actuator is failing.

NHTSA ID

11744859

Incident

May 27, 2026

ABS, traction control, brake system, and brake lights turned on while driving. Took the car to the mechanic and pulled the code C1391. It seems from other complaints to NHTSA that it is a common issue and quite dangerous, meaning the brake system is failing.

NHTSA ID

11741205

Incident

May 25, 2026

ABS, brake, and traction warning lights came on. Loss of power brakes/limited manual brake. Extended warranty/customer service outreach did not apply. Car is at 120,000 miles and almost 12 years.

NHTSA ID

11740747

Incident

May 19, 2026

When the brake is applied, the vehicle accelerates for a fraction of a second before slowing down. I have experienced this when the vehicle is moving slowly, such as in a parking lot.

NHTSA ID

11738043

Incident

Mar 9, 2026

On April 5, 2026, while driving downhill around a corner in my 2014 Toyota Prius, the brake booster and brake booster pump assembly failed without any prior warning. When I pressed the brake pedal the car did not slow down and instead appeared to accelerate due to a complete loss of braking assist. I was unable to stop the vehicle normally and had to rely on gravity and coasting to slow down, creating a serious risk of collision. There were no warning signs prior to the failure. Immediately after the incident, three warning lights illuminated on the dashboard: the BRAKE light, the ABS light, and the VSC (vehicle stability control) light, which have remained on since. The vehicle was taken to DARCARS Toyota Baltimore, 6007 Eastern Ave, Baltimore, MD 21224, where the failure was confirmed on April 15, 2026. Technician Victor Lawson diagnosed diagnostic trouble code C1391, which is the exact qualifying code listed under Toyota's Customer Support Program ZJB for brake booster and brake booster pump assembly failure (RO# XXX). The vehicle remains at the dealership and is available for inspection. Toyota corporate was contacted and opened case number XXX but declined to cover the repair despite this being a documented issue that Toyota has publicly acknowledged. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11731351

Incident

Apr 5, 2026

While driving, three warning lights suddenly appeared on the dashboard . Abs warning, traction light, and break warning light At the same time, the brake pedal became very hard to press, and the vehicle did not slow down as expected. This caused a significant increase in stopping distance, and I nearly rear-ended the vehicle in front of me. The issue appears to involve the braking system and created an immediate safety risk. No prior warning signs were noticed before this incident. The vehicle has not yet been inspected but is available for inspection upon request.

NHTSA ID

11729306

Incident

Apr 5, 2026

Subject: Brake Booster/Pump Assembly Failure – Toyota Program ZJB / 23TE07 Description of Incident: I am reporting a failure of the brake booster and pump assembly on my 3rd Generation Prius (82,000 miles). While the vehicle is 11.3 years old, it is well under the 150,000-mile threshold of Toyota’s Customer Support Program ZJB. The brake pump began cycling every 13 seconds, indicating an internal pressure leak in the accumulator. This is a documented precursor to a total loss of power-assist braking. Despite the clear mechanical failure, no warning lamps or Diagnostic Trouble Codes (DTCs) were triggered, creating a safety hazard where the system could fail without prior electronic notification. Repair and Cost Details: Because the vehicle was 1.3 years past the arbitrary 10-year "Secondary Coverage" window, I was forced to pay $3,461.18 out-of-pocket for a known manufacturing defect. I would like to highlight a discrepancy in labor billing: while Toyota’s own technical bulletins (ZJB/23TE07) state the repair should take approximately 5.3 hours, the dealership charged 8.9 hours of labor for the same procedure. Safety Concern: By limiting coverage to 10 years, Toyota has left many low-mileage owners with a critical safety defect that degrades over time regardless of mileage. I request that the NHTSA transition this from a "Customer Support Program" to a formal Safety Recall to ensure all affected vehicles are repaired and owners are reimbursed, regardless of the vehicle's age.

NHTSA ID

11726119

Incident

Mar 18, 2026

the cylinder head gasket blew because of the poor design of the intake manifold and the EGR system. There are updated parts to fix this issue, but there was no recall. This poor design led to the vehicle having "the Death Knock." It started doing this knock on my trip driving my daughter to college. The engine could have seized in traffic on the way to [XXX] from [XXX] . No warning lights came on telling me there was an issue. The vehicle is being taken apart now to see if my connecting rods were bent from the coolant entering the combustion chamber. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11724395

Incident

Feb 28, 2026

The contact owns a 2014 Toyota Prius. The contact stated that while driving at an undisclosed speed, the vehicle failed to slow down as intended with the brake pedal depressed. The ABS warning light was occasionally illuminated. The vehicle was pulled over to the shoulder of the roadway and restarted. The vehicle was taken to a local independent mechanic, where it was diagnosed, and determined that the brake master cylinder, brake booster, and brake lines needed to be replaced. The local dealer was contacted; however, the vehicle was not diagnosed or repaired. Upon further investigation, the contact related the failure to an undisclosed recall; however, the VIN was not included in the recall. The manufacturer was notified of the failure. The contact was referred to the NHTSA Hotline for assistance. The failure mileage was approximately 152,000.

NHTSA ID

11724167

Incident

Mar 13, 2026

Mileage

152,000 mi

Vehicle: 2014 Toyota Prius v Hybrid Mileage: 79,000 miles The vehicle experienced sudden failure of the brake booster / brake accumulator system. Multiple warning lights appeared including ABS, traction control, and the red brake warning light. Diagnostic code C1391 was retrieved. The brake pedal became soft/spongy and the electric brake pump began cycling frequently. Braking performance felt reduced and inconsistent, creating a potential safety risk. This vehicle has very low mileage (79,000 miles) and has been well maintained. The failure appears to be related to a known defect in the Prius braking system. Toyota previously issued Customer Support Program 20TE07 addressing brake booster and pump failures on 2012–2014 Prius v vehicles. Despite this known issue, the repair is not being covered and the cost quoted is several thousand dollars. A failure of the brake booster/accumulator system significantly affects braking performance and should not occur at this mileage. This appears to be a widespread issue affecting Prius vehicles and represents a potential safety defect involving the braking system.

NHTSA ID

11722125

Incident

Mar 2, 2026

Head gasket failure. No check, engine, light or warning. My car was very well maintained regularly. After research, I found this to be a very common problem. Yes it is available for inspection. Upon request. The problem was confirmed by chemical test, ignition vapors going into engine coolant. Other symptoms were misfiring on cylinder two and cylinder four. Severe engine knocking.

NHTSA ID

11721338

Incident

Mar 1, 2026

The brake booster/accumulator failed on my vehicle. This part was a common failure during the 2010-2015 production run so much so that Toyota extended coverage to replace. Mine failed recently beyond the warranty extension of 10 years/150k miles. My vehicle has only 108k miles and is 15 months beyond warranty. Toyota Corporate will not replace this vital part, despite the fact it was a defective design. I can’t drive it any longer since I don’t have the $4000 to make repair. Toyota Corporate has shown little concern despite this critical safety defect.

NHTSA ID

11716906

Incident

Feb 2, 2026

The slip notification, abs, and brake lights turned on while driving on the highway. The brakes then became very stiff and the vehicle did not brake as fast or as well as it normally does without the lights.

NHTSA ID

11715358

Incident

Feb 3, 2026

2014 Prius HB with 135k miles , onboard system warning lights for Brakes, ABS system, TPMS and Traction Ctrl all came one suddenly. Brake losing pressure while vehicle making strange noise under front driver side

NHTSA ID

11714327

Incident

Jan 29, 2026

On Jan 5, 2026 I was driving locally at about 40-45 mph. All of a sudden 3 indicator lights came on ABS, Brake, and Brake System Warning Light. There were no noises, but the brakes felt different. They did stop when needed. I left space between myself and others just in case, did not want an accident. Called my regular mechanic. They advised to not drive the car, but to bring it into the shop at 8am the following day. On Jan 6th, the mechanic stated it was beyond their expertise. It was towed to the local Toyota Dealer for repairs. It ended up being the Brake Booster and Pump. Upon investigation online, we saw this was a recall, but we were not notified by Toyota.

NHTSA ID

11713896

Incident

Jan 5, 2026

I was driving on the freeway, and a few lights(including ABS, brake lights) all came on and a beeping noise started, as i immediately lost complete control of my brakes! That God it was late, and no cars were in front of me. The car slowed down as I removed my foot of the gas right away. I tried to pull over as soon as I heard the lights, and that’s when I realized my brakes were completely gone! I was able to stop after about two miles; car stop on its own as it slowed down. Apparently, this was a major known issue and had warranty up to 150k miles. At the time of the incident, my car had about 165k miles. I had the car for years, and no one at the dealer ever mentioned anything about this or even tried to make me aware of it! I called the Toyota dealer and corporate number several times and they declined providing me with any help at all! This caused me fear and traume because I never thought this was possible! It could’ve ended my life and the life of people around me if there were any cars in sight! The problem has been confirmed by a reputable mechanic! He did the repairs! He also called the Toyota dealer and corporate and attempted collecting anything since he found out about the warranty and common issue. They also denied help. No lights were on at all before this incident happened! It all came at once! I even have all records of monthly/ bimonthly complete inspections at the dealer with everything normal on the results!

NHTSA ID

11711583

Incident

Dec 8, 2025

Hello, We were informed that the vehicle paint had a recall due to paint chipping. Unfortunately we never received the notice and was unaware until after the recall program had ended. We are contacting you now to see how we can address this issue as our vehicle paint is chipping all around the car.

NHTSA ID

11711167

Incident

Feb 11, 2025

The brake booster system (electric brake booster pump) in my 2014 Toyota Prius has been making frequent, audible cycling noises inside the cabin, particularly during cold weather. I have also noticed a faint odor outside the vehicle that seems related to electrical movement. No ABS or brake warning lights have illuminated, but the cycling pump may indicate increased stress on the brake system. The issue has not yet been diagnosed or confirmed by a dealer or independent service center. The problem has not caused a loss of braking ability to date, but the unusual noises and electrical odor suggest potential risk if the booster were to fail completely. No recall or customer support program currently covers this issue. The component is part of the vehicle’s brake system and would be available for inspection by a dealer or manufacturer upon request. Toyota has offered no help or possibility of Goodwill assistance inspection for this issue.

NHTSA ID

11709692

Incident

Jan 8, 2026

The brake system malfunctioned suddenly. While driving and while stopped, the brake pedal became very hard and braking behavior became unpredictable. The vehicle sometimes brakes aggressively and other times requires excessive pedal force to stop. The ABS and BRAKE warning lights illuminated. The vehicle no longer provides normal braking assistance. This issue is related to a failure of the brake actuator / brake booster, which is a known issue affecting Toyota Prius models from 2010 to 2015. This defect creates a serious safety risk, as braking performance is inconsistent and may increase stopping distance or cause loss of control during emergency braking situations. The vehicle has not been repaired yet because the cost is very high and the manufacturer has declined assistance despite this being a known safety-related defect.

NHTSA ID

11707101

Incident

Dec 12, 2025

misfire code along with rough starts/light load. T-SB-0116-15

NHTSA ID

11706254

Incident

Dec 18, 2025

My 2014 Toyota Prius (VIN [XXX] , 77,000 miles) displayed Brake, ABS, and Slip warning lights. A mechanic confirmed failure of the Brake Booster and Pump Assembly (DTC C1391). Toyota previously acknowledged this as a safety-related defect under Customer Support Program ZJB, but my coverage expired because I never received Toyota’s notice dated May 21, 2019. My car has been undrivable for weeks and Toyota refuses goodwill repair. This is a serious brake safety issue that should be reviewed for recall or extended coverage since many Prius owners have experienced the same failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11696950

Incident

Oct 13, 2025