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Gen 3 Brake locking up while I am driving

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by joshmuluba, Nov 11, 2023.

  1. joshmuluba

    joshmuluba New Member

    Joined:
    Oct 9, 2023
    5
    0
    0
    Location:
    New York
    Vehicle:
    2012 Prius
    Model:
    Four
    Gen 3 - Brake locking up while I am driving. A few months ago, I bought a used 2012 prius and it was driving fine with hybrid battery change code P0A80 but car drove fine without any issues. A week later, I decided to buy a scanner tool (bluetooth dongle device) . I noticed a few codes along with P0A80 , C1345, C1368, C1445, C1451, U0073 and B27A2. I bought ebay techstream version, the same codes confirmed with techstream. I decided to perform Learning Linear Valve offset with techstream. After the test completed, I didnt get a change to test as it was late but I left the emergency brake on. The next morning, My wife decided to drive the car to work when she returned home she told me about a beeping sound as she drove the car. Side note: This car dashboard has all lights work fine except the braking lights dont work ( ABS, VCS and Traction control). There was no way for her to be alerted on dashboard about brake light was on. I connected techstream and scanned no code popup, but I went to analysis screen showed all 3 lights were on (ABS/vsc/trac). I cleared all codes however all codes disappeared except the U0073 and B27A2. I did more online research regarding the U0073, a few ppl mentioned they had the same issue with odb dongle torque pro so I thought everything was fine since I had both dongle and torque pro apps. The main issue started the next day as I was driving around as soon as the steering felt weird (drifting one side) then both front brakes locked up (the wheels make the squeaking noise, I almost went thru the windshield) and there was a sound as if the engine felt down on the road but there was nothing under the car when I checked. The car couldnt go forward or reverse so I turned it off / on everything was ok. I thought it was one off issue so I ignored it. the next few days I drove it work as I was trying the same steering behavior then the same braking behavior almost threw me to the windshield. I was lucky not getting into car accident. I took it to dealership so they claimed wheel alignment is the cause so I paid them about $300 for diagnostic and wheel alignment. As soon as I left the dealership, the same issue happened, I returned to the dealership and asked for a loaner as they continue troubleshooting the issue. A few days later, they called me and said they couldn't pin point the issue but they were also getting the same code of U0073 and strongly suggested to replace the ABS actuator and pump for $2500. I declined so I it took home to check a few things myself before replacing an expensive part. I jacked up the car with 4 tires off and put car in drive mode on - I noticed left wheel dragging while right wheel spins a bit faster than drive side and techstream also confirmed the wheel speed not matching. I am now processing replacing wheel bearings on both sides, rotors and pads. hopefully it resolves the issue. I head so great things about this car but it is now scary driving it. Please post any advise before I cough out $$$ to buy ABS actuator as I am reluctant believing the issue to be ABS actuator.
     
  2. joshmuluba

    joshmuluba New Member

    Joined:
    Oct 9, 2023
    5
    0
    0
    Location:
    New York
    Vehicle:
    2012 Prius
    Model:
    Four
    BUMP - before I replaced the ABS as dealer recommended, I used ebay techstream and got details on U0073 as noticed Wheel angle reporting sensor angle by 320 degrees. I remembered a split sec right before the issue occurs the steering would feel weird as if the car was going off center. I am definitely certain my issue related to steering wheel sensor angle is not aligned correctly. The techsteam shows the angle sensor is working and reporting the steering degrees. Please advise if I should replace Angle sensor / clock spring , ABS actuator /ABS pump - I attached the U0073 code detail
     

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