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Car alarm randomly going off

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by parrot_lady, Aug 27, 2010.

  1. parrot_lady

    parrot_lady Member

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    Hey guys and gals,

    I have an issue, and I don't know if it's kids, animals, or the car itself. Last night it happened at 3am, tonight I'm sitting on the couch at 12.30am and it just went off again....

    I don't see anyone out there around the car, not sure I saw anything last night either. Is there a cause for this? I just replaced my 12v battery in March, have a dead FOB smart key in a fire box (it's up on top of everything in the box). My current key was lying flat on the bench, nothing on top of it.

    I'm getting aggravated. I don't want to tick my neighbors off, and I'm starting to think it's the local kids, but I want to know if anyone else has gone through this.

    This is the dealer installed alarm (useless, yet very annoying at this point). I had it installed when I bought the car and it has paid me back on insurance already.

    TIA, Amy
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Vehicle:
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    Two
    Who knows what alarm your dealer installed. Nevertheless, some general comments:

    The key question is whether or not someone or something is causing the car alarm to trigger. Only you can figure that out, by watching the car.

    If you decide that the alarm is triggering on its own without someone or something causing it, then for the sake of neighborhood tranquility you may want to have the alarm removed, or at least have the motion sensor and/or glass breakage sensor disconnected. Good luck.
     
  3. firepa63

    firepa63 Former Prius Owner

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    Do you have the glass breakage alarm (from Toyota)? If so, have the dealer disable it. It has been known to cause mysterious alarms like you are describing.
     
  4. korat102

    korat102 New Member

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    I had this problem on my 2005 Prius after I'd had it a year. The dealer changed what they called a 'head unit' which fixed the problem.
     
  5. parrot_lady

    parrot_lady Member

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    So it feels like its been a while, and after reading through here again I'm having the SAME problem, roughly a year later.


    Quick Check of the charge on the battery indicates no issues, so I decided to pull the glass break sensor and see if it solves anything. Now, I've had this glass break sensor installed TWICE because the first time the tape they used quit and the damn thing wound up falling off. When it fell it looked like a foam covered mic... today when disconnected it There was NO FOAM COVER on the mic. I'm wondering if that makes any difference in how the mic perceives/picks up sound.

    The quirky thing about the car alarm going off is it happens randomly the first time, and then within 7 hours, it goes off again- either right at the 6 hour mark or at the 7 hour mark. It doesn't matter if its parked in the garage or the driveway, and I haven't moved. We've added one more vehicle to the family since then, and I don't think thats an issue.
     
  6. KayakerNC

    KayakerNC Member

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    Vehicle:
    2010 Prius
    Model:
    III
    Have the dealer check out the hood sensor.