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Where is the gen 3 Prius door switch wire (to tap-in factory alarm)

Discussion in 'Gen 3 Prius Accessories and Modifications' started by Jenny2010Prius, May 14, 2022.

  1. Jenny2010Prius

    Jenny2010Prius Junior Member

    Joined:
    Apr 24, 2017
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    Location:
    Calgary
    Vehicle:
    2024 Prius Prime
    Model:
    SE
    I just couldn’t find the Gen 3 (2010) Prius door switch wire under the driver side step sill.

    Considering rampant Catalytic Converter theft these days, I decided to install a DIY tilt alarm with mercury gravity switches. The plan is simple, just tap in the door switch wire in the existing factory alarm system. The diagram shows it clearly.
    DIY_tilt_alarm.png
    Loosed door switch, and confirmed the wire is a thin brown one.
    IMG_20220514_171150342.jpg

    Opened up the step sill and found dozens of wires. There are 2 brown wires. Stripped them one by one and did tests. None is the door switch wire, as one of the brown wirings is always ground no matter if the door is closed or not, the other one never connected to ground.

    IMG_20220514_171308107_HDR.jpg

    Does anyone have any ideas or advice?
     
  2. ChapmanF

    ChapmanF Senior Member

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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
  3. tony_2018

    tony_2018 Member

    Joined:
    Jun 12, 2019
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    Location:
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    Vehicle:
    2012 Prius
    Model:
    IV
    There are dedicated sites that can help, one is 'the12volt'. You can also google search 'alarm wiring' for your specific car but you'll still need a dmm to test/verify wires.
     
  4. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
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    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    LR1 probably pin 54
    EC0456AD-7167-45A0-ACF8-13EB5D816A7B.jpeg