2015 Toyota Prius V service brakes problems

“The brake booster assembly failed, as many of these models had before. A bunch of codes went off as I was driving and the brakes did not function properly. Toyota had an extended warranty for this which they discontinued last year and they would extend no good will towards the $4,000 repair”

“The ABS, BREAK, and Traction Control, suddenly turned on when I was traveling on the freeway in mild traffic. I was traveling at about 60-65 mph. I attempted to use the breaks and could feel a substantial difference in how much and how hard I had to push in order to stop. The problem has not been confirmed by a dealer or service center. The vehicle was inspected by my brother in law who works on cars frequently. There were no warning symptoms prior to the problem. The problem first occurred on Saturday November 1st at about 12:30. According to my brother in law, it was the break pump that failed; you can hear air escaping when you push on the break pedal.”

“Emergency Brake, Traction and ABS warning came on and stayed on in addition to a five-second interval cycling on of a motor sound under the hood. O'Reilly Auto Parts and then Toyota dealership confirmed the same code that indicated brake booster assembly needs replacing (C1391) **This is a "known issue" but not yet a recall. Toyota did extend the part warranty to 10 years or 150,000 miles - my vehicle has only gone 85,500 and unfortunately is eight months into the 10th year and Toyota is refusing to cover any portion of the repair. I would like to be part of the effort to have this formally declared a recall because I got the quote today to replace the brake booster assembly and it's going to cost half the value of the vehicle! $4000 is the low estimate Bighorn Toyota gave me to do the repair/replacement. Thank you for your help!”

“Brake booster failed. ABS lights on. Brake light on. Traction control light on. Was sitting at stop with foot gently on brake when lights turned on. Attempted to restart car to clear lights, lights would not turn off after normal restart x3. Brake no longer function correctly, and the factory installed ABS are no longer functioning. Braking distance greatly increased, and no longer as safe to operate.”

“While driving my Prius on the highway, the ABS and traction control warning light suddenly came on. The brakes started feeling different right away, and it didn’t feel safe to drive. I took it to a Toyota dealership, and they found that the brake booster and pump had failed. I looked online and saw that many other Prius owners had the same issue, so it doesn’t seem like an isolated case.”

“2015 Toyota Prius ABS warning light came on . Went to car mechanic . Brake Actuator & Pump code leaking. It happen on 7/27/25 under 100,000 miles. Currently Anti Sway and ABS braking disable.”