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Multiple lights and codes on 2009 Touring

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by tollkeen, Mar 4, 2024.

  1. tollkeen

    tollkeen New Member

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    Vehicle:
    2009 Prius
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    Four Touring
    Several months ago, my tire pressure light came on and would not go off. I did the manual reset, checked pressure, and light stayed on. I assumed sensors were bad but I would replace in the future.

    About a week ago, several lights were on when I started it for the first time in the AM - parking brake, brake system light ("!" in a circle), ABS, VSC, and tire pressure light (but that one has been on). A code scan pulled up these: C1391 - Abnormal leak of ACC pressure, C1256 - Accumulator Low Pressure Malfunction, and C1241 - Low Battery Positive Voltage or Abnormally High Battery Positive Voltage.

    Nothing noticeable with normal driving. Brakes are braking.

    Where should I begin?
     
    #1 tollkeen, Mar 4, 2024
    Last edited: Mar 4, 2024
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    Touring
    Do a search for brake actuator failure. Unfortunately, it's a relatively common failure on the Gen 2. There's probably a thousand threads on it inside this forum that will help you come up to speed understanding what is happening. Hope this helps!
     
  3. ChapmanF

    ChapmanF Senior Member

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    The C1241 code is a complaint about the voltage arriving at the brake system to power it.

    It doesn't have to mean a problem with the 12 volt battery; it can also be a problem along the wiring path and connectors serving the brake system.

    But the 12 volt battery is an easy first thing to check when you have that code.

    The C1391 and C1256 would ordinarily be bad news about the brake actuator. But find out what's up with its power supply first, since you have that other code. If the power is inadequate, that can be a reason the accumulator pressure takes too long to build up.