2009 Toyota Prius driver assistance problems

Filed Jun 17, 2026 · Brakes, Driver assistance · CT

Dashboard Warning Lights: ABS, VSC, Parking Brake Light, Triangle with Exclamation Point, Codes: C1256 & C1391, Intermittent Audible Cabin Buzzing indicating critical pressure loss on start-up for about 10 seconds...then stops, not loss so much as anti-braking quick bursts at about 5 mph of stopping v slowly and seamlessly coming to a stop. I contacted Toyota Corporate Case Management; they refused to escalate or remediate the issue due to vehicle mileage, despite being notified of the active brake pressure leak codes and the audible safety alarm.

Filed Apr 25, 2026 · Brakes, Driver assistance · OK

Brake actuator is broken. Toyota knew about this problem and they had a warranty for 10 years or 150k miles. Mine only has 80k miles. The repair is half of what the car is worth. I thought a Toyota with such low miles would be dependable. Toyota knew that people have died from this problem with their car. I need this car to get to work and get my kids to school. It’s older than 10 years so I am just screwed on something they knew was broken. Of course the sales person at the Toyota dealership did not tell us about it when he sold us the car

Filed Apr 2, 2025 · Driver assistance, Electrical · NJ

Breaking system failure do to ASB Actuator, breaks are locking and vehicle is engine braking.

Filed Dec 5, 2024 · Brakes, Driver assistance · TN

In the 2009 Toyota Series II vehicle there are two parts for the brake actuator pump assembly which has been cycling about every 20 seconds for the past six months or more. There is an intermittent tone when depressing the brake pedal before starting the car (engine off). The Brake dash warning light is on continuously. Occasional loss of brake power in reverse causing the driver to re-apply the brakes to stop unwanted motion of the vehicle.

Filed Oct 9, 2024 · Brakes, Driver assistance · WA

The engine light went on while driving on the highway. We immediately pulled over and had the vehicle towed to the nearest dealership. The dealership informed us that both the Brake Actuator (Toyota part TO44500-47141) and water pump (Toyota par TOG9020-47031) had failed. The car was no longer save to drive.

Filed Feb 8, 2020 · Brakes, Driver assistance · 177,000 miles · CA

Upon starting the vehicle it makes a high-pitched beep, followed by a buzzing sound that repeats every five to eight seconds. The dashboard displays the tps, ABS, vsc, and brake lights. When putting the vehicle in drive, the high-pitch sound returns for one to two minutes. During that time the brake pedal becomes impossible to depress. If the engaged, the vehicle does not stop until the brake pressure returns. Once the sound stops, the brake pressure returns to normal. Diagnosis from toyota shows: code c1256 = accumulator low pressure. Code c1391 abnormal leak of accumulator pressure. Estimate for repairs = $2,811.72. At present the vehicle is unsafe to operate as toyota advised, in the vehicle's current condition the brake system could fail at any time.

Filed Feb 10, 2017 · Driver assistance, Electrical · 70,000 miles · CA

Traveling 101 north toward ventura, on the top of the down hill grade just south of the camirillo springs exit. All lights on panel came on. Estimate 65 MPH, applied brake to slow with traffic flow. No brakes,no warning.semi tracker trailers also slowing. Took exit bottom of hill with flashes on, went thru stop sign as my speed at approx 45-48mph. Went thru second stop sign made sharp left pulled emergency brake on... This is a garage car serviced by dealer only, 3rd time for electrical problem! Never while driving.... This was near fatal! This was an electrical problem of the manufacture, never repaired correctly! Have 3 copies of repairs for the electrical starting 6 months after purchase car...help.

Filed Dec 13, 2013 · Brakes, Driver assistance · 110,000 miles · TX

As I was driving my 2009 toyota prius on the service road of I-30 in dallas around 25 MPH after previously taking off from a red light, my vehicle's warning lights all turned on and started to beep and I could not brake or really steer. My vehicle...I almost hit the vehicle in front of me. Somehow I was able to turn right into a parking lot and somehow press on the brakes strong in enough to make the car stop. I feared for safety and the safety others as well. It was a very scary situation to be in a car that was not responding when you are trying to break and there's nothing you can do about it. Once I was in the parking lot, I turned the vehicle on and off and the lights were still on and beeping, did it again and it stopped. I took the car to the toyota dealership and they are telling me it's an issue with the accelerator and brake system and that I have to pay to have it fixed, but I am wondering how can toyota not be at fault for this safety issue? I'm glad I didn't injure myself or another person this time, but I think toyota really needs to look into this issue with their prius vehicles. I do not feel safe driving mine at all now.....they can not get away with not being responsible and liable for their faulty and defective vehicle's safety mechanisms.

Filed Nov 19, 2013 · Brakes, Driver assistance · 71,500 miles · NJ

The vehicle braking lost braking momentarily when I was driving over small bumps and vehicle slip sign illuminated.

Filed Jul 5, 2010 · Driver assistance · 25,000 miles · PA

My 2009 toyota prius, since I first purchased it april 2009, the anti-lock brakes seem to fail. When I brake and hit a bump in the road the anti-lock brakes engage and release the brakes. It feels as if I am sliding on ice. I discussed this with the toyota dealer last month, who dismissed this as normal anti-lock brake activity. I feel these cars need to be recalled and repaired.