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sensor or other device on hood latch

Discussion in 'Gen 2 Prius Technical Discussion' started by tomctomc, Nov 25, 2012.

  1. tomctomc

    tomctomc Junior Member

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    i had to remove/repair my hood latch (cable broke) on my 2008. there is a 2-wire sensor or similar device mounted to the latch. what is its purpose? i broke the wires to it - yet see no evidence that any system ceased to work as a result. i want to make sure it isn't something critical. thanks
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    This probably is the outside air temperature sensor used by the air conditioning system and reported by the MFD display. See what exterior air temperature is reported by your MFD.
     
  3. tomctomc

    tomctomc Junior Member

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    thank you Patrick - i also suspected this and checked the outside temp reading. its 32 degrees in Boston this morning and that is what the reading says. it could be a coincidence, of course, with 32 being 0*C... Since it apparently was not the temp sensor I thought i would ask the forum...
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The OAT sensor is mounted on a vertical beam in front of the radiator. It sounds like your MFD temp reading is normal, so maybe the sensor you are referring to is a switch that tells the body MFD or an aftermarket alarm that the hood has been opened?
     
  5. tomctomc

    tomctomc Junior Member

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    there is no mechanical connection or association with the latch mechanism... don't think it is a switch. this device is simply mounted to the latch frame. nothing aftermarket on the car, either. It could be a terminated connector block (though a bit unusual looking) for diagnostics or some unused accessory. there are two wires going to it. thanks for your thoughts

    terrible picture, but this thing is obscured when the latch is installed:

    http://i1234.photobucket.com/albums/ff419/tomctomc/hoodconnector.jpg

    the device is in the exact center of the picture, what appears to be one white cylinder stacked on another (sort of look like cigarette butts)
     
  6. Air_Boss

    Air_Boss Senior Member

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    OAT displays often report OC ("Open Circuit", not to be confused with "0 degrees C") when the sensor or wiring are not present.
     
  7. nh7o

    nh7o Off grid since 1980

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    I think that device is the "Engine Hood Courtesy Switch" which is connected to the theft deterrent system. It honks the theft deterrent horn if forced. If it is not a mechanical switch then it could be a magnetic, proximity type.
     
  8. tomctomc

    tomctomc Junior Member

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    thanks - i arrived at the same conclusion. there is no mechanical interface with the latch, so its either a magnetic switch as you suggest or it is a connector which has terminated without any connection at all. in any case, i can confirm that the wires which have been cut and taped off have not caused any loss of functionality in the car at all..