2008 Horn Won't Stop :o help!

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by AmberMarie, Feb 27, 2022.

  1. AmberMarie

    AmberMarie New Member

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    This morning I turned on my car and sat there for a second, THEN I pressed the AC Auto button on my steering wheel and my horn went crazy! We pulled the fuse with #10 on it and it stopped, but now the AC Auto button doesn't work and my fuel gauge and the "mi" on my odometer are blinking? Idk, I think my car is goin crazy. Please help!

     
    #1 AmberMarie, Feb 27, 2022
  2. bisco

    bisco cookie crumbler

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    start by testing the 12 volt battery
     
    #2 bisco, Feb 27, 2022
  3. PriusCamper

    PriusCamper Senior Member

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    Is it possible a foreign substance or physical damage happened to AC and horn switch?
     
    #3 PriusCamper, Feb 27, 2022
  4. AmberMarie

    AmberMarie New Member

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    update: We put the fuse back in and it was silent, but I pressed the AC auto button and my horn honk so I did it again and the the AC auto button work as normal but when I honk the horn the horn started running again so we had to pull the fuse back out. For some reason this time the AC auto button is working even with the fuse out
     
    #4 AmberMarie, Feb 27, 2022
  5. AmberMarie

    AmberMarie New Member

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    i'm not sure, how could i see this?
     
    #5 AmberMarie, Feb 27, 2022
  6. bisco

    bisco cookie crumbler

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    weird.
    i have read that when the hazard lights won't shut off, it is because debris is jumping 2 pins on the ecu, and cleaning solves the problem
     
    #6 bisco, Feb 28, 2022
  7. ChapmanF

    ChapmanF Senior Member

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    The hazard-lights thing is Gen 3-specific, and has a very special signature: the hazards blink faster the faster you drive!

    So far, I don't think anyone has successfully solved the Gen 3 hazard thing by cleaning anything. The most recent fixes have been by clipping one of the involved wires.

    If there is a good lesson to be carried over from a Gen 3 hazard thing to a Gen 2 horn thing, it won't be so much "here's what the Gen 3 hazard thing turns out to be", but "careful study using the wiring diagram was how the solution was found, and that's also what will work here."
     
    #7 ChapmanF, Feb 28, 2022
  8. PriusCamper

    PriusCamper Senior Member

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    Trying again... Are the buttons loose or sticky?
     
    #8 PriusCamper, Feb 28, 2022
  9. mr_guy_mann

    mr_guy_mann Senior Member

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    You should get the service manual and wiring diagram so you can diagnose this. My money is on something like two circuits in the clockspring are (partially) shorting together.

    Posted via the PriusChat mobile app.
     
    #9 mr_guy_mann, Mar 1, 2022
    dolj and PriusCamper like this.
  10. dolj

    dolj Senior Member

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    That was my initial thought as well.
     
    #10 dolj, Mar 2, 2022
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