2013 Toyota Prius

Year/Make/Model: 2013 Toyota Prius • Component: Brake Booster Assembly with Master Cylinder (Part #47070-47060) Description of the Defect: After approximately 30–40 minutes of driving, my dashboard illuminates with the Brake, ABS, and VSC warning lights simultaneously. The brake pedal becomes inconsistent and requires significantly more effort to stop the vehicle. This is a known internal fluid leak within the brake booster assembly that causes the accumulator pump to run continuously and ultimately reduces braking performance — a direct safety hazard. Why This Requires Federal Attention: This is not an isolated incident. Hundreds of 2013 Prius owners have reported identical symptoms, with associated diagnostic trouble codes C1391, C1252, C1256, and C1253. Toyota acknowledged this defect by issuing Technical Service Bulletin TSB-0089-20 and a Customer Support Program (ZJB) providing limited extended warranty coverage. However, that program was not well publicized . I was never informed as a vehicle owner . And it has now expired, leaving thousands of owners with a dangerous defect and repair bills costing thousands . A safety defect of this magnitude — one that can result in sudden, significant loss of braking ability — should not have an expiration date on its remedy. Toyota has not issued a mandatory recall, and owners continue to unknowingly drive vehicles with compromised brake systems. Requested Action: I respectfully urge NHTSA to: 1.Open a formal investigation into this defect across all affected 2013–2015 Toyota Prius model years 2.Require Toyota to issue a mandatory safety recall 3.Compel Toyota to cover repair costs for all affected owners regardless of mileage or age of vehicle

The brake actuator/ABS hydraulic system on my 2013 Toyota Prius failed. The component is available for inspection upon request, as it was replaced by a Toyota dealership. Prior to failure, the vehicle intermittently displayed ABS, Traction Control, and VSC warning lights while driving, which would sometimes clear on their own but eventually became persistent. This condition reduced or disabled ABS, traction control, and vehicle stability functions, increasing the risk of loss of control or reduced braking effectiveness, particularly in emergency braking or low-traction conditions. The problem was reproduced and confirmed by a Toyota dealer, who diagnosed the failure using diagnostic code C1391 indicating internal brake actuator malfunction. The vehicle was inspected by the manufacturer’s authorized dealer, who replaced the brake actuator assembly after three days of repair at a cost of approximately $3,000. Warning lamps were present for months prior to the final repair and gradually progressed from intermittent to constant, indicating a worsening failure of a known issue affecting this generation of Prius vehicles.

On [XXX], we were driving from Coalinga, CA to Phoenix, AZ for Thanksgiving. As we began to descend into Los Angeles on [XXX], three warning indicators suddenly went on: the ABS warning light, the traction control light and the brake warning light. The brakes still worked but the brake assist was weakened. We pulled over as soon as possible at the nearest AutoZone. The employee performed a standard handheld OBD-II scan of the vehicle and did not detect any issues. We continued on our way through Los Angeles and to San Bernadino where we were spending the night. At one point the indicator lights went off for a few minutes but then came back on. We spent the night in San Bernadino, and the next day (11/26/2025), we took the car into the San Bernadino Toyota Dealership as we felt it was unsafe to keep driving. The dealer conducted a thorough full brake and hybrid system diagnostic and confirmed that the failure was inside the brake booster system. The repair estimate states: "Brake booster assembly with master cylinder and brake booster pump assembly have an internal leak." Thus, Toyota's own technician identified an internal hydraulic leak within the booster system, affecting the booster assembly, master cylinder, and booster pump assembly. The total repair estimate is $3,959.99. This is a major safety defect affecting sealed hydraulic components that are not part of routine wear-and-tear. There were 4 people in the car. Fortunately, the brake failure did not result in an accident, but it could have if we had kept driving on to our destination. We contacted the Toyota Brand Engagement Center to ask for Goodwill Assistance, but they were unable to help us. In addition to the repair costs, we have incurred rental car costs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The brake booster assembly (part number 47070-47060) on my 2013 Toyota Prius has failed. This component is critical to the proper functioning of the braking system. It is currently still installed in the vehicle and available for inspection upon request. As a result of the failure, the ABS warning light, traction control light, and brake warning light are all illuminated on the dashboard. The braking performance has noticeably declined — the pedal feels inconsistent and at times unresponsive. This has created a significant safety risk while driving, especially during sudden stops or in wet conditions, as it compromises the vehicle's ability to brake efficiently and predictably. The issue has been confirmed by a Toyota dealer (or independent mechanic if that’s the case — feel free to change this line accordingly). The dealer diagnosed the issue as a failure of the brake booster assembly, which aligns with known failures reported by many other 3rd-generation Prius owners. The vehicle has not been involved in an accident, and has not been inspected by the police or insurance representatives. Toyota previously issued a Customer Support Program (CSP ZJB or ZG1) covering this part, but it has since expired. I only recently began experiencing symptoms and was unaware of the CSP until after contacting Toyota. Prior to the warning lights, I experienced intermittent symptoms such as a soft or delayed brake pedal, and an unusual sound from the brake system when the vehicle was turned off. The warning lights first appeared around [insert approximate mileage or date here], and have remained illuminated since then. Given the safety-critical nature of this component and the known defect history, I am requesting assistance from Toyota in the form of goodwill coverage or reimbursement, and would like this issue escalated for further review.

My car is at 89K total miles and last week I had three warning lights pop up on my dash (Traction control, brake, ABS) which indicates something wrong with the automatic break system. My car is under 100K miles and I purchased it used in 2016, under ten years ago, and this problem is way too early to happen in my make an model. I got a code read on the issue (C1391) which indicates that my ABS Actuator is leaking/broken, a major safety issue as it happened as I was driving. Again, this should not be typical as I only drive a few miles per day on average.

The 2013 pruis has developed the notorious brake booster fault triggering the brake light abs light and traction control light to stay illuminated. Toyota has many complaints about this brake booster issue and needs to recall and fix this issue as they have done on other Toyotas. This is leaving owners with a $2500 repair or having to take a big risk driving these cars with a big prevalent brake issue that Toyota needs to be held accountable for.