2014 Toyota Prius v

I purchased a 2014 Toyota Prius V in 2013, and it currently has 120,000 miles on it. Last month, the engine light came on, so I took it to a dealership. They diagnosed the issue and provided the codes P0302 and P0304. After consulting multiple shops, all confirmed that coolant is leaking into the engine, which means I either need to repair the head gasket or replace the engine entirely. The quotes I've received for this repair range from $5,000 to $15,000, while the current value of the car is only about $5,000. I want to file a complaint regarding Toyota's responsibility for these engine issues. We buy cars because we trust the brand, and in this case, Toyota has broken that trust. Despite maintaining the car according to Toyota's recommended schedule, I have encountered this serious problem.

Description of the Problem Vehicle: 2014 Toyota Prius v (Mileage: 70,000) Problem Description: The vehicle is experiencing a critical failure of the Electronically Controlled Braking (ECB) system, specifically the Brake Actuator and Booster Pump assembly. The dashboard currently displays multiple warning indicators: ABS light, Traction Control light, and the Brake System Warning light (Master Warning "!"). Symptoms: Mechanical Failure: The internal high-pressure accumulator is failing to hold pressure. The electric brake booster pump is heard cycling (straining) every 10–20 seconds even when the vehicle is stationary and the brake pedal is not depressed. Loss of Braking Safety Features: The system has disabled regenerative braking and Anti-lock Braking (ABS), causing significantly increased stopping distances and a "wooden," unresponsive brake pedal feel. Predictability of Failure: This failure matches the exact symptoms described in Toyota’s Customer Support Program 20TE07 (and previously ZJB), which acknowledges an internal defect in the brake actuator. Safety Risk: The sudden transition from power-assisted braking to manual hydraulic braking during a drive creates an immediate safety hazard. As the pump motor continues to cycle excessively to compensate for the internal leak, it is at risk of total thermal failure, which would lead to a near-total loss of braking assist while the vehicle is in motion. Additional Notes: Despite the vehicle having only 70,000 miles (well under the 150,000-mile limit acknowledged in Toyota’s support programs), Toyota has declined to provide assistance because the vehicle has surpassed the 10-year age mark. I am filing this report because a primary safety component (brakes) should not experience catastrophic internal failure at 70,000 miles, regardless of the vehicle's age.

I have 2014 Prius v 5 with 100,000 miles but I had issues with brake booster pump

8/2025 Car stalled on freeway. Went to dealer. They said nothing wrong. Then on a trip north, car stalled again on freeway. Went to the nearest dealer. They too said nothing wrong. This time same thing. There is a recall for the exact symptoms of the exact car yet they say the repair was done. Why does my vin not qualify for the exact symptoms that generated a recall? This was super dangerous at freeway speed. Toyota knows there is a problem with the inverter and it's computer. Now I'm paying again for a diagnosis. That makes $750 just diagnosing and now if they actually decide it is the inverter, I have to pay upwards of $3000 even though there is a recall? What the heck?

The brake booster has failed and seems to be a common issue with this model vehicle for Toyota issued an extended warranty, but I am passed the date and they are unwilling to do anything. Due to the malfunctioning brake booster. The car is unsafe to drive the too expensive to repair.

Brake booster is not working

The contact owns a 2014 Toyota Prius V. The contact stated that while driving approximately 35 MPH, the brake light, tire pressure, traction control, battery, and other warning lights were illuminated. While attempting to depress the brake pedal, there was more resistance than normal, making it difficult to slow the vehicle. The contact was able to drive the vehicle to the nearest mechanic; however, the vehicle was not diagnosed. The vehicle was then taken to the residence. The vehicle was taken to another certified mechanic, who diagnosed and determined that the brake master cylinder and actuator assemblies had failed. The brake master cylinder and brake actuator assemblies were in the process of being repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 220,000.

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)

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.

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.

C1391 - Abnormal Leak of ACC Pressurization. Bad Brake booster assembly.

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.

There was a safety recall issued for brake system malfunctions involving the brake booster and brake booster pump assemblies on my vehicle. Unfortunately, the recall expired on December 31, 2024. On March 4, 2025, at 4:10 PM, I contacted the District Manager Advocate in Plano, Texas. I explained that I had been in the ICU twice and am now [XXX]. During the recall period, I was in and out of hospitals for more than four years, making it impossible for me to be aware of or respond to the recall in time. My vehicle has since begun exhibiting the exact symptoms outlined in the recall. When I brought this to their attention, I was told that while the issue was indeed covered under a past recall, there is nothing they can do now because it has expired. This vehicle is our only mode of transportation, which is critical for my ongoing medical treatments, as well as for my husband who recently suffered a heart attack. As I write this, we have no other option but to continue using the vehicle—despite the serious safety risk—because of the urgent and necessary care both of us require. On August 4, 2025, I contacted Toyota headquarters. They reached out to the dealership and spoke with management, but unfortunately, no resolution was offered except for information about a separate, newer recall. I followed up again with the District Manager and spoke with Ashley, who informed me that after escalating the case, there was still nothing further they could do and she expressed her apologies. This situation has caused further deterioration to my health due to the stress and anxiety of potential vehicle failure, and it has added to the burden of my husband’s fragile health condition. At this time, he has been unable to return to work, and we have no income to cover the cost of a repair that should have been addressed through the original recall. We would deeply appreciate any assistance, reconsideration, or compassionate review of our case. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ABS Brake pump actuator booster failed. It is available for inspection. While driving, I started hearing a hissing sound from my brakes. I tried to slow down and my several diagnostic lights (ABS, traction control, brake, check engine, etc.) flashed on while my brakes failed to work properly. I turned on my hazard lights immediately. I was in the middle of the road with my toddler in the car and I almost rammed into the car in front of me. Luckily I was able to pull into a turn lane and pushed with all my might on the brakes and it finally was able to stop. My brakes failed and I could have hit the cars in front of me and hurt my child, myself and others. It was terrifying. Problem has been confirmed by an independent service center. The warning lamps only appeared WHILE the issue was happening and my brakes failed to work properly.

The car stalls randomly and does not enter fail-safe mode. The dealer says it is the transmission but the transmission has never shuddered or hesitated. I am reading that these vehicles have intelligent power modules in the hybrid inverter that fail and can cause stalling. I feel like the dealership is working with Toyota to avoid addressing the actual problem. In the meantime I was sent home in a vehicle that continues to stall randomly and does not enter fail-safe mode.

I am writing to express my profound concern and disappointment regarding a recent, terrifying incident involving the brake system of my 2014 Toyota Prius. On Saturday, June 21, 2025, while driving with other passengers, my vehicle experienced a complete and sudden brake failure. Multiple warning lights illuminated on the dashboard, and despite my efforts, the brakes became unresponsive, making it impossible to stop the car. The sheer terror and helplessness I felt in that moment, with the very real potential for a catastrophic accident involving myself, my passengers, and other road users, is indescribable. Fortunately, through sheer luck and quick thinking, I was able to make an emergency stop on the side of the road, preventing any collision or injury. However, the emotional toll of that experience, the lingering stress, and the fear of a recurrence remain significant. I was subsequently informed that the cause of the failure was a leak in the brake accumulator. I am attaching the diagnosis and repair invoice. The necessary repairs were not completed until Wednesday, June 25th. This unforeseen and critical malfunction also necessitated the expense of a rental car for four days, adding to the financial burden and inconvenience. My frustration is compounded by the fact that this brake accumulator issue is a well-documented and known defect in Toyota Prius models, specifically affecting 2010-2015 vehicles. Toyota itself has previously issued a Technical Service Bulletin (TSB T-SB-0043-13) acknowledging this problem and offering warranty extensions for affected vehicles, typically up to 10 years or 150,000 miles. Despite this being a recognized safety concern, I was informed that my vehicle falls approximately eight months outside the 10-year warranty period, thus disqualifying me.

While braking on the interstate, this car threw error code C1391: Abnormal Leak of ACC PRESS. This is the brake system accumulator pressure - meaning lost all assistance to braking - it took a long time to slow down and come to a stop. Easily could have caused a serious crash had I been on a hill or coming up on stopped traffic. I did some research and found this is a KNOWN ISSUE with Toyota and SHOULD HAVE BEEN A RECALL! Toyota skirted the issue by offering customers that encountered the problem a CUSTOMER SERVICE PROGRAM where they would pay for a new brake pump and master cylinder. HOWEVER, Toyota put TIME and MILEAGE CONSTRAINTS ON THE PROGRAM, and it just so happened our car had exceeded those limits - so we had to pay full price for the repair of the 2 new brake parts - over $3,000! The 2014 Toyota PriusV that we bought new and had always serviced it properly was hardly worth that, but it was our only car, so we paid it. BUT will never buy another Toyota now - and NHTSA needs to fine Toyota for this poor brake system

Upon exiting the highway my brake system when engaged was completely unresponsive. I of course pushed down gently as would and upon realizing the brakes were not responding I started pounding on the brake pad. I had to ram the brake down for the vehicle to even slow. Thankfully no-one was in front of me at the light and I was able to pull into the nearest gas station having to ram brake to fullest extent to get the vehicle to stop moving. All lights within the braking system lit up including the Master Warning Light, Brake System Warning Light, ABS Warning light, and SLIP indicator as well as the warning siren. These warning lights did not come on til after* the brake system was engaged with failure*** NOT PRIOR. It was not indicative of an issue prior too, no former brake issue or warning lights. I turned the vehicle off and then back on again to see if the same lights still lit and issue was still malfunctioning. I called for a tow and had vehicle taken to the Adams Toyota Dealership (MO)The following diagnostic code C1391 was registered on my vehicle at dealership. Upon research (not disclosure) I found that the above code- C1391- "Brake booster and Brake Booster Pump Assembly" is a known issue that Toyota offered a Warranty repair from May 21-Nov 22' IF FAILURE Not a recall but a "if" brake system fails. Please see Customer Support Program 21TE01. I purchased vehicle in OCT 21 and was never informed, never provided this warranty letter, issue didn't show up on Carfax etc and I purchased directly from the Toyota Dealership. Upon research you will find that Toyota is currently in class action and individual lawsuits re this specific part failure with the above diagnostic code. They are denying replacement due the expired warranty time. The Parts should recalled* not just a "warranty issue" -unacceptable to leave buyers uninformed to such a major issue that can cause accident/death (IM PREGNANT I MAY ADD!) and unable to seek covered repairs unless it fails!

The vehicle stalled while driving 35 to 45 mph. Engine had no power but the brakes and power steering worked.

While driving my 2014 Prius V it stalled. I turned it off and restarted it. The yellow car symbol with an exclamation point lit up. I turned the car on and off again. The light went away and I was able to drive home. I was unable to get any OBD 2 codes on my personal reader. I changed the 12 V battery and thought this had fixed the stalling. Then it stalled again and repeated the same process. Though we were able to drove the car I had it towed to a dealership for safety reasons. The dealership pulled codes, cleared them, drove the car 20 miles, and were unable to reproduce the codes. I was told to return when the codes returned. It stalled again and now I am afraid to drive this car.