2015 Toyota Prius

Problem: Brake Actuator is pulsing the Booster Pump to keep running intermittently, 5-10 seconds. Console lights lit up for ABS problem. Does not clear. Toyota Dealership Report: DCT C1391 Abnormal Leak: Monitored TEH Accumulator Pressure and its not holding pressure. Pump keeps running. Rec[ommend] Brake Actuator and Booster Pump Assembly [replacement].` ServCo Toyota dealership in Hawaii Report: Submitted Prior Authorization request with Toyota Hawaii Warranty. Request Denied for Goodwill Coverage on ABS Actuator and Booster Pump.

On XXX, I was driving my 2015 Toyota Prius with my family in the vehicle and approaching stopped traffic on dry pavement. An emergency vehicle was approaching from behind, so I began braking earlier than usual. When I applied the brakes, the vehicle did not stop normally. The front slowed/stopped while the rear of the Prius suddenly slid sideways toward the adjacent lane, bringing the rear passenger side dangerously close to another vehicle. Had I begun braking at my normal stopping distance, I believe a collision would have occurred. No crash or injuries occurred, but the incident was extremely dangerous. I drove the vehicle very slowly to Purrfect Auto Services, [XXX], where the brake/ABS system was diagnosed. I observed diagnostic code C1391. The shop has had the vehicle since XXX and has experienced repeated problems with used replacement brake-system components that were defective or would not function properly. The vehicle has remained unsafe to return to service while the shop works to obtain a properly functioning replacement part. I am reporting this because the sudden and unpredictable braking behavior created a serious risk to my family and other motorists. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Code DTC C1391 - Abnormal leak of accumulator pressure. Internal failure of the brake booster pump assembly, preventing the system from maintaining proper hydraulic pressure. This means the brakes don't work, putting the driver's and passengers' lives at risk. This DTC C1391 code and problem were reproduced and confirmed by an independent service center who specializes in 3rd generation priuses. There were warning lights that lit up when the brakes failed - the ABS, traction control, and brake light all lit up but only after the brakes had stopped working. This is a known manufacturer defect but toyota won't pay to fix it because they put a 10 year limit on first driven date or 150,000 miles. This prius only has 100k miles but toyota still won't stand behind their product even though they have admitted it was a manufacturing defect and they sold a defective product.

I was rear-ended by a truck in my prius and my seat laid back on impact. I'm unaware if that was an intended thing or not but it potentially could have injured my neck. My car is currently in a storage lot awaiting the adjustor's inspection so it is available for inspection if needed. No warning lights were available and it hasn't been recreated by the dealer

Pulling out of a parking stall, when put vehicle in drive, the engine revved up and accelerated - vehicle crashed, the brakes did not work- there was skid marks. Floor mats are factory OEM were installed properly. I did not hit the accelerator and I am in good health and mind. I have driving for over 30 years, never had and accident nor a ticket! - A county officer was at the seen and left me with vehicle that had to be towed away. The Vehicle is a total loss. I have insurance but felt that this incident need to be reported, There is no safety recalls and the vehicle was always property maintained

The vehicle experienced a failure in the braking system involving the brake booster/brake actuator assembly. The vehicle displayed diagnostic trouble code C1391, which is associated with a malfunction of the brake booster pump/accumulator system on this model. The failed component is available for inspection upon request. The failure created a safety concern because the braking system warning lights illuminated and the vehicle’s brake assist system may not function properly. A malfunction of the brake actuator/booster system could increase stopping distance, reduce braking performance, and create a potential risk of a crash, especially during emergency braking situations. The problem has been confirmed through diagnosis showing the C1391 trouble code. The issue has been identified as a brake system malfunction requiring repair of the brake booster/actuator assembly. The vehicle has been inspected/diagnosed by a service professional. The vehicle has not been inspected by police or insurance representatives. Toyota/dealer inspection information is available if requested. I contacted Toyota regarding the issue, but they declined assistance because the extended warranty coverage expired approximately 7 months prior to the failure. Before the failure, the vehicle operated normally. The first symptoms occurred when multiple warning lights appeared while driving, including the ABS warning light, brake warning light, parking brake warning light (even though the parking brake was not engaged), and the traction control/slippery road warning light. These warning lights appeared suddenly, indicating a problem with the braking system.

The contact owns a 2015 Toyota Prius. The contact stated that while driving and coming to a complete stop, the vehicle was rear-ended by another vehicle driving approximately 35-45 MPH. The contact stated that upon impact, the front driver's seat unexpectedly reclined and struck the rear passenger’s seat. The contact was concerned about the movement of the seat and stated that an occupant seated directly behind the driver's seat could have been injured. The rear bumper, trunk, and rear body structure sustained damage from the crash. The contact stated that the force of the impact caused the rear driver’s side body panels to flare outward and become deformed. No additional property damage had occurred from the crash. The vehicle remained in the roadway following the crash. There was no warning light illuminated. The contact sustained neck injuries, whiplash, and emotional trauma from the crash. Medical attention was sought. The Uber passenger inside the vehicle was also transported from the scene to seek medical attention and treatment; however, the extent of the injury was unknown. The contact considered the vehicle a total loss by the contact, but the vehicle was not declared a total loss. The vehicle was towed to a tow yard. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 205,000.

The contact owns a 2015 Toyota Prius. The contact stated that while driving at 45 MPH, the brake warning lights illuminated. The brakes were inoperable and entered manual mode. The contact stated that the brake warning lights were red and yellow. The vehicle was taken to Brake Masters, where it was diagnosed with brake actuator failure. The local dealer was contacted but did not provide assistance. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 121,000.

The incident involved having to press extremely hard on the brake pedal to stop the car, while it was uphill in the middle of the road. The car started going backward and was throwing ABS, Master Warning Light, Brake System Warning Light and Warning Buzzer, Brake System Warning Light, and SLIP Indicator signals. This was a highly distraughtful situation on the road. Diagnostics showed C1391 Diagnostic Trouble Code on the 2015 Toyota Prius: brake booster and brake booster pump problem. When pressing the brake pedal there is a high pitched metal scraping noise. Toyota coverage program is only applicable for 10 years from the date of first use or 150,000 miles, whichever occurs first. Many cars run well for over 10 years with good care, so the 10 year cap barely covers anything. This is highly unfair and borderline scamming for an issue so severe, which can cause big accidents on the road. In all honesty, this is a life or death situation when it comes to not being able to properly brake while driving. This should be a full recall!!

The brake pump and actuator on my 2015 prius has been faulty and the repair was apparently covered under the customer support program but it expired in December. I had no knowledge of it and when I took my car in to a toyota dealership, no one told me about about the profram but told me that they needed to be replaced. I did not get the repair because of the hefty cost and I missed the deadline. My safety and the safety of other drivers were put at risk for not allowing me to be notified by it and my car being at risk for my brakes failing at any time. Their were absolutely no warning lights on my vehicle as well.