2015 Toyota Prius

I was driving my 2015 prius for years and occasionally the brake, abs and traction light would come on this is a sign of a failing Brake actuator and booster. Toyota and the Ntsb ordered the following warranty enhancement https://static.nhtsa.gov/odi/tsbs/2020/MC-10181800-9999.pdf My Brake Booster had been exhibiting signs of failing for years and I tried to get a toyota dealership to replace and repair the parts under the warranty extension but I was told I had to wait until I had perminent dash lights and trouble codes. So I had to wait till the booster completely failed. By that time my car had exited the extended warranty perimeters and I am told it is no longer eligible.... even though the components are faulty from the factory and exhibited signs of failure many years prior. I was told to wait until the compenent failed by multiple dealers. My car was in motion and the brake boosters failed, fortunatly it did not cause an accident but this is a serious safety issue. Toyota should have done a compleat recall of the brake actuator and booster pump, rather than have drivers use known faulty components until failure. Toyota corporate has refused to help in the repair of the vehicle despite it showing failure for years.

Toyota Prius has a known problem with the brake actuator and booster. A notice was sent out in 2019 under the Customer Support Program Expansion with repairs up to 10 years or 150k miles. This is a safety issue and should be covered under a recall with NO TIME OR MILEAGE LIMITS since these problems are not showing up until after 10 years if the car has low mileage, as in our case. We just passed the 10 year mark, but only has 114k miles. No mention of repairs needed were made during regular maintenance visits with Toyota. Additionally, preventative repairs were not offered if the vehicle did not seem to be experiencing problems at that time. The brakes are spongy and unresponsive. The ABS light , traction warning lights, and parking brake lights are staying on.

On 4/16/26, while driving my 2015 Toyota Prius (approximately 87,000 miles) on the freeway, I applied the brakes while transitioning from the [XXX] onto the [XXX] . As I veered right on the curved onramp, the brakes failed to engage properly, causing the vehicle to spin out of control and collide with the side railing. There were fortunately no nearby vehicles on the 2-lane onramp at the time. Under slightly different circumstances, this incident could easily have resulted in serious injury or death to myself and/or others. No airbags deployed. Although I was physically unharmed, I was extremely shaken by the incident. Immediately after the collision, the brake warning light, ABS warning light, and another warning indicator illuminated on the dashboard. Prior to the incident, I had not experienced braking problems severe enough to suggest imminent failure. On 4/17/26, I brought the vehicle to Toyota of Cerritos for diagnostic evaluation. I was informed that the brake booster was the issue and that the vehicle was unsafe to drive. The vehicle was towed to a collision repair center affiliated with my insurance company. After repairing the external collision damage, the collision center informed me that the brake booster malfunction that caused the incident could not be repaired there and would require dealership service. External repair alone: $3706, in addition to increased automobile insurance premiums expected over the next 3 years. I also contacted Toyota Motor Corporation regarding Customer Support Program coverage related to brake booster issues and was informed that the program expired in 2025 and no assistance would be provided. I am submitting this report because this brake booster malfunction created a serious and unexpected safety hazard resulting in loss of vehicle control on a freeway interchange. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My brake actuator and brake booster are failing. All of my dashboard lights have come on (brake, ABS, Traction Control, brake system warning light). Unfortunately, I am over 10 years and Toyota is saying that I need to pay out of pocket for the repairs. This is a known problem and should be covered. I was unaware of the known issue and my car didn't start having problems until after the 10 year mark. I am under 150,000 miles.

In June 2025, while driving on the highway, the vehicle suddenly displayed multiple brake warning lights and warning messages, including the red brake warning light, ABS light, brake system warning light, and traction/slip indicator. At the same time, the brake pedal became stiff and braking effort increased suddenly, creating a near-crash situation because the vehicle did not slow normally. Before that incident, the vehicle had already been making abnormal brake-related noises, including a humming/pumping noise when the brake pedal was applied, and there were intermittent episodes where braking felt abnormal. In June 2025, the vehicle was taken to a Toyota dealership during Toyota’s brake booster support program period. The dealership documented customer complaints of “humming noise in cabin when holding foot on the brakes,” a request to “scan for codes for ZJB enhancement,” and that the “vehicle hard to accelerate and brakes got stiff,” but stated that no qualifying ABS codes were present at that time. In March 2026, the same condition returned and worsened. The vehicle again displayed the red brake warning light, ABS light, brake system warning light, and traction/slip light, and braking performance was reduced. An OBD scan of the ABS control unit showed code C1391, which is associated with brake booster / ABS actuator failure. The Toyota dealership has now diagnosed the vehicle with ABS actuator and brake booster failure and quoted repair. This is a serious safety issue because braking became more difficult while driving, including on the highway, with sudden warning lights and degraded stopping ability. The failed components are available for inspection. The problem has now been confirmed by a Toyota dealership. The issue was reported to a Toyota dealership during the prior support-program period but was not confirmed then.