Brake actuator failure, coded as C1391. known issue by Toyota which can result in loss of brakes if not repaired. symptoms of problem: pulsing air sound from master brake cylinder, and/or all braking system lights illuminate on dash.
2014 Toyota Prius V
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2014 Toyota Prius V do not stand out strongly from the model-year median of 20.
About this comparison →How this year compares
Owner complaints by model year
Compare all Prius V years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
34 reports with mileage · 48 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Service Brakes. Review the 38 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Electrical System. Review the 15 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine. Review the 13 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
82 reportsBrakes failed to stop vehicle for over almost ½ of a block. The driver, a young woman, was so terrified that she is refusing to drive the car even after the brakes have been repaired. It is my understanding that Toyota is aware of this problem and has issued directives for its dealers to make the necessary repairs. However, I …
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Brakes failed to stop vehicle for over almost ½ of a block. The driver, a young woman, was so terrified that she is refusing to drive the car even after the brakes have been repaired. It is my understanding that Toyota is aware of this problem and has issued directives for its dealers to make the necessary repairs. However, I was told that this was extended to 150,000 miles or 10 years from first in service date. I am including the invoice from Lipton Toyota for over $4,000 and I am respectfully requesting that Toyota makes this right and refunds this money. The failure of a braking system represents a critical life threatening situation of which no one can deniy.
I have a 2014 Toyota Prius V. I was driving down the highway at 55 m/h when my brakes became spongy all of a sudden and the ABS, traction and brake lights came on the dashboard. I was very scared and seeing that my brakes were failing I almost caused an accident that could have cost my life and my family's. I managed to get home…
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I have a 2014 Toyota Prius V. I was driving down the highway at 55 m/h when my brakes became spongy all of a sudden and the ABS, traction and brake lights came on the dashboard. I was very scared and seeing that my brakes were failing I almost caused an accident that could have cost my life and my family's. I managed to get home safely and after scanning the system got the code C1391 - ABORMAL LEAK IN ACCUMULATOR. I did some research and this defect is so well known that Toyota launched a costumer program to replace the booster for free. I took it to a Toyota dealership and they wont't replace it though because the program expired a couple of months ago. This is an expensive and life-threatening part. The defect comes from the manufacturing facility, not from usage, so Toyota should be responsible for it.
I am a US military member stationed in Germany. I bought my Toyota Prius V used, in 2020, knowing I'd be stationed in Europe and expressly because of Toyotas reliability and Prius's great mileage. This was our family's third Prius and a sixth Toyota vehicle. It's been almost exactly 2 years since my family moved to Germany, whe…
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I am a US military member stationed in Germany. I bought my Toyota Prius V used, in 2020, knowing I'd be stationed in Europe and expressly because of Toyotas reliability and Prius's great mileage. This was our family's third Prius and a sixth Toyota vehicle. It's been almost exactly 2 years since my family moved to Germany, when one day I was driving through a small town, below the speed limit of 35 mph (50 km/h). Suddenly, while driving, the red BRAKE light, yellow ABS light, and red brake system warning lights came on all at once. The car's brake continued to work normally but I also started hearing a low volume, frequent, 1-sec long electronic buzzing sound coming from somewhere the front of the car, on the driver's side. It was audible every 3 seconds or so, even after the car was put in Park and turned off, then it went off after a couple minutes. I took the car to a local German Toyota leadership to have the problem diagnosed. The Service Department told me later that day the DTC1391 was identified, and the brake booster assembly + brake booster pump assembly needed to be replaced, at a total cost of this repair being over EUR 9,000 (around $9,900). The parts themselves were quoted to cost EUR 3,500 and EUR 4,000 each, and would have to be ordered from the US. I cannot afford to pay $10K to repair a 10-year old car. After some research, I discovered while Toyota never issued a recall, they knew about this brakes problem since 2018. I found several "Customer Support Program" notifications to Prius owners for this specific problem, including the one numbered 20TE07 which applied to 2012-2015 Prius's V. It told dealers to do this repair free of charge and extended the coverage for 10 years or 150,000 miles It also had info on repair cost reimbursement to customers. Hoping I could get my car fixed and file for reimbursement I called Toyota US and was told this CSP expired in Mar 2024 for my VIN and that there was nothing Toyota would be able to do.
Four warning lights related to the braking system illuminate, followed by what seems to be the cessation of the ABS. After 5 minutes of driving, the lights went off and abs returned, although brakes are shaky. The abs seems to be a known faulty park and is covered under warranty but only up to 150,000 miles. When taken to a de…
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Four warning lights related to the braking system illuminate, followed by what seems to be the cessation of the ABS. After 5 minutes of driving, the lights went off and abs returned, although brakes are shaky. The abs seems to be a known faulty park and is covered under warranty but only up to 150,000 miles. When taken to a dealer, the repair shop recommended I call corporate. Citing the arbitrary mileage limit, the Toyota mechanic seemed convinced the corporate office would cover the cost, saying he’s seen it done on a case by case basis. This coverage should be made unilaterally for all car owners with this defect, not simply those willing to fight for it. Class action lawsuits over what seems to be a similar issue have been privately settled.
The contact owns a 2014 Toyota Prius V. The contact stated that the vehicle was previously involved in two car crashes, where the vehicle rear-ended other vehicles due to the brakes failure. The air bags did not deploy. A police report was filed after the second crash, but the information was not available. The contact stated th…
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The contact owns a 2014 Toyota Prius V. The contact stated that the vehicle was previously involved in two car crashes, where the vehicle rear-ended other vehicles due to the brakes failure. The air bags did not deploy. A police report was filed after the second crash, but the information was not available. The contact stated that the other driver sustained unknown injuries during the second crash. The vehicle sustained damages and was repaired. There was no further information provided. Additionally, the contact stated while driving at various speeds and depressing the brake pedal, the brakes made an abnormal sound and the brake pedal was spongy. The contact stated that the vehicle hesitated to respond. The ABS warning light and several unknown warning lights were illuminated. The vehicle was taken to the dealer, where it was diagnosed that the brake booster had failed and needed to be replaced. The dealer informed the contact that it was a known failure; however, the repair could not be covered because the vehicle had a salvage title. The vehicle was not repaired. The manufacturer was notified of the failure and a case was opened. The failure mileage was approximately 120,000.
Completely unannounced and sudden brake failure, which caused a failure in the traction control and ABS system as well. Most likely brake actuator pump failure.
2014 Toyota Prius V [XXX] [XXX] (17:45 CST) Sudden loss of braking ability. Brake pedal goes nearly to the floor. Nearly caused collision. ABS, BRAKE, VSC and Orange Exclamation Point Warning all indicated simultaneously. Brake ABS pump / actuator makes buzzing sound audible in driver seat about every 5 seconds. CSP/TSB…
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2014 Toyota Prius V [XXX] [XXX] (17:45 CST) Sudden loss of braking ability. Brake pedal goes nearly to the floor. Nearly caused collision. ABS, BRAKE, VSC and Orange Exclamation Point Warning all indicated simultaneously. Brake ABS pump / actuator makes buzzing sound audible in driver seat about every 5 seconds. CSP/TSB coverage apparently expired 75 days ago. Occurred at mileage 152,589. Open case with Toyota # [XXX] Vehicle not yet inspected by dealer. Vehicle is available for inspection upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Hands free controls were deactivated on vehicle. No longer able to use Blue tooth. This presents a safety hazard.
The contact owns a 2014 Toyota Prius V. The contact stated that while driving at an undisclosed speed, the brake pedal was firm which made it hard to stop the vehicle. No warning light was illuminated. The vehicle was diagnosed by a dealer, and it was determined that there was a leak in the brake booster pump assembly. The vehic…
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The contact owns a 2014 Toyota Prius V. The contact stated that while driving at an undisclosed speed, the brake pedal was firm which made it hard to stop the vehicle. No warning light was illuminated. The vehicle was diagnosed by a dealer, and it was determined that there was a leak in the brake booster pump assembly. The vehicle had not been repaired. The manufacturer was made aware of the failure and informed the contact that parts to repair the vehicle was not available. The failure mileage was approximately 142,000.
Official recalls
420V369000 · Hybrid Propulsion System: Inverter
Jun 24, 2020
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2013-2015 Prius and 2014-2017 Prius V vehicles not included in recall 18V-684. Excessive voltage in the Intelligent Power Module (IPM) within the inverter may cause the hybrid system to shut down, causing the vehicle to stall while being driven.
Consequence & remedy
Consequence: An unexpected hybrid power system shut down may increase the risk of a crash.
Remedy: Toyota will notify owners, and dealers will perform a software update for the hybrid system. If the vehicle has experienced an inverter failure with certain hybrid system faults related to this condition, the inverter assembly will be repaired or replaced, prior to software update. All repairs will be performed free of charge. This recall began July 24, 2020. Owners may contact Toyota customer service at 1-888-270-9371. Toyota's number for this recall is 20TB10 / 20TA10.
18V684000 · Hybrid Propulsion System
Oct 4, 2018
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2010-2014 Toyota Prius and 2012-2014 Toyota Prius V vehicles. Excessive voltage in the Intelligent Power Module (IPM) within the inverter may cause the hybrid system to shut down, causing the vehicle to stall while being driven.
Consequence & remedy
Consequence: If the hybrid system shuts down unexpectedly, it can increase the risk of a crash.
Remedy: Toyota will notify owners, and dealers will update the software for the motor/generator control electronic control unit (ECU) and the hybrid control ECU as necessary, free of charge. The recall began January 22, 2019. Owners may contact Toyota customer service at 1-888-270-9371. Toyota's number for this recall is J0V. Note: The software updates in this recall are needed even if the vehicle had the software previously updated under recalls 14V-053 or 15V-449.
15V449000 · Hybrid Propulsion System: Inverter
Jul 15, 2015
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2012-2014 Prius V vehicles manufactured August 22, 2011, to June 30, 2014. A component within the hybrid inverter assembly may overheat, causing the hybrid system to reduce output power allowing the vehicle to only drive a short distance. In some circumstances, the hybrid system may shut down causing the vehicle to stop while being driven.
Consequence & remedy
Consequence: The vehicle may enter a fail-safe/limp-home mode that limits the drivability of the vehicle. The hybrid system could also shut down completely resulting in a vehicle stall, increasing the risk of a crash.
Remedy: Toyota will notify owners, and dealers will update the software for the motor/generator control electronic control unti (ECU) and the hybrid control ECU, free of charge. The recall began on July 30, 2015. Owners may contact Toyota customer service at 1-888-270-9371.
15V013000 · Air Bags
Jan 16, 2015
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2014-2015 Toyota Prius V vehicles manufactured November 7, 2013, to January 7, 2015. The occupant classification system (OCS) that activates or deactivates the passenger seat air bag system may be improperly calibrated. As a result, the passenger air bag may not deploy in a vehicle crash. As such, these vehicles fail to comply with Federal Motor Vehicle Safety Standard (FMVSS) No. 208, "Occupant Crash Protection."
Consequence & remedy
Consequence: If the air bag does not deploy as intended, there is an increased risk of injury in the event of a crash.
Remedy: Toyota will notify owners, and dealers will re-calibrate of the OCS system, free of charge. The recall began February 12, 2015. Owners may contact Toyota customer service at 1-800-331-4331.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
0No exact-year investigations in this snapshot.
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