Brake Master Cylinder problems of the 2011 Toyota Prius

I have an early year 2011 Toyota Prius, the break booster and master cylinder assembly work intermediately. Sometimes it shows errors with lights illuminated on the dashboard and brakes have a lot of play and are spongy and other times they work perfectly normally. The vehicle was in motion and when I went to use the breaks in a traffic situation they ended up hardly working putting myself in a higher risk for a collision and putting my life endanger.

Toyota had a customer support program zjb for default brake booster/master cylinders on the 2010 Prius models. I have a 2011 Prius that has been diagnosed with the same problem and there is no customer support offered. This warranty enhancement on the 2010 models is good thru 11/30/19 regardless of mileage. Even though my vehicle has the exact problem there is no recognition for support due to the year of this vehicle. I was not aware I even had a problem until I took it to the dealer for a software recall update. We were experiencing heavy rain and my indicator lights came on which is why they checked this and confirmed the issue although my brakes are working fine. I am not understanding why Toyota is not honoring the fix for the default or why after discovering this issue in 2010 the 2011 would not be considered. I would appreciate some help in this matter.

The following is a summary of how I became aware of the power booster and master cylinder problem with my 2011 Toyota Prius. �upon discovery of multiple lights displayed on dashboard such as brake, abs system & traction lights, during driving the braking performance has changed drastically & the car no longer performs braking function adequately. Unable to rely on safe braking due to brake resistance felt with stiffening in which pedal depresses deeply & more time is required to come to a full stop. When braking the hybrid battery does not charge & runs dangerously low resulting in damage to the hybrid battery which can lead to substantial cost to replace the battery. �car brought to firestone for diagnostics. Upon further inspection by their technician it was determined that the power brake booster/master cylinder was damaged & malfunctioning and was in need of replacement. Informed repair would be in excess of $1,500. 00. See enclosed supportive documentation from firestone diagnostics.

I was moving forward in a turn lane on a city street preparing to make a left turn. A vehicle cut in front of my car and it was necessary to make a quick stop to avoid an accident. Immediately red warning lights lit up indicating a problem with the brakes. The repair statement from the dealer indicated that the brake booster with master cylinder assembly had failed and needed to be replaced. The repair required over two weeks to complete and I was informed that the procedure in the service manual for repairing the problem was incorrect.