ABS,PCS,BRAKE, Slip Indicator, Brake system warning lights on

Discussion in 'Prius v Care, Maintenance and Troubleshooting' started by genna1119, Mar 3, 2025.

  1. genna1119

    genna1119 New Member

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    2012 Prius v wagon
    Model:
    V
    Need some Help as I am very concerned and confused after reading threads on this.... I have a 2012 Prius V with around 47,000 miles on it. Had it for around 6 months. I started hearing a humming noise intermittently a couple of weeks ago. I hit a pothole (I believe) 3 days ago. Humming started increasing yesterday ( every minute or so) and today (every 5-10 seconds) after the lights came on today. I was driving all day and in the afternoon they came on. Car also seemed to jump a bit forward when I put it in Park. Braking takes a longer push down to stop after lights came on. Checked brake fluid and I am full. Was not able to take it anywhere to check for codes. Could I have caused damage to something expensive to fix when I hit the pothole or could this be something else that surfaced? Thank you.
     
  2. rjparker

    rjparker Tu Humilde Sirviente

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    Vehicle:
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    Odds are it's your Brake Booster (Master Cylinder) Assembly. It is a common issue that was covered by a special warranty up to ten years.

    It is an expensive part and somewhat difficult to install and setup via Techstream scanner software. Usually it is a $2400 job at a dealer.

    There will be specific codes but most auto supply scanners can't read them. If you are not advanced diy I would find an independent hybrid or Toyota specific shop.

    Expired Customer Support Program
    https://static.nhtsa.gov/odi/tsbs/2019/MC-10158577-9999.pdf

    Prius Brakes FAIL (Hidden COST of Hybrids)


    IMG_7694.jpeg

    Current online Toyota dealer part price is around $1200 - used is not recommended as there are several versions per model year. Vin verification of part is needed.

    The following part number is 47050-47110 for a 2012 Prius v wagon trim 3. A trim 5 will be different as will all Prius hatchbacks and the Prius c.
     

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    #2 rjparker, Mar 4, 2025
    Last edited: Mar 4, 2025
  3. genna1119

    genna1119 New Member

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    Location:
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    Vehicle:
    2012 Prius v wagon
    Model:
    V
    Yes, that humming/buzz noise is exactly what I hear. I have the trim 5 so I am waiting to hear from a local independent Toyota shop who serviced my car previously for an appointment. Ouch....the cost. I am thinking I will be okay getting it to the mechanic about 10 minutes away versus towing it? But I will make sure they diagnose and let me know what they find and I want new parts. Strange as I looked in the manual that was in the car and all the icons that showed up on dashboard have a pencil check mark in the book. Wonder if this was replaced early on by previous owner (perhaps with a used part).... and somehow never logged in the records for a repair/recall replacement? Used part went bad? When the car was inspected overall by 2 toyota mechanics, they both stated it was in excellent condition. Neither mentioned anything about brake issues and I did ask... Can this booster issue just surface all of a sudden? Know this may sound crazy but I have to ask....could someone with a lot of knowledge sabotage this somehow? Some damage to my interior happened in the car and with some items that were inside. Been ongoing since I got the car. Getting cameras at this point but I have to ask. Thank you for the information.
     
  4. rjparker

    rjparker Tu Humilde Sirviente

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    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    There is an increased frequency of brake pump operation that is sign of potential issues, often starting weeks or months ahead. But it does not code until the hydraulic brake pump can not keep up.

    I know of no way to sabotage the brake by wire system. However it is a common failure on gen3s.

    There are methods to change the mileage on the combination meter. Your 2012 would have been averaging 3600 miles a year at 47k miles or allowed to sit for a very long time.