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Lost Dumb-Key functionality after replacing key fob shells

Discussion in 'Gen 2 Prius Main Forum' started by Tom Farrell, Jul 15, 2023.

  1. Tom Farrell

    Tom Farrell Junior Member

    Joined:
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    2007 Prius
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    II
    I have successfully programmed a replacement Smart-Key fob before, so I'm no asking about that. In this situation, I bought new shells for both my key fobs and, after I had replaced both, I found that, while the Smart-Key functionality was fully intact, the Dumb-Key functionality was gone.

    To be clear, while I could still start the car while my key fobs were in my pocket, I could no longer do so while they were inserted in the dashboard. (I suppose this is an anti-theft feature?) So ... without a master key possessing Dumb-Key functionality, it would appear that I have totally lost the ability to program ANY key fob to possess that ability? Would anybody disagree with that and be able to help me regain Dumb-Key functionality?

    Or do I just have to accept being the dummy who can get his car to start so long as the battery in my key fobs have not gone dead? (Meaning I'd always have to carry a spare CR2032 cell ad tiny screwdriver in my car.))

    Any help would be greatly appreciated.
     
  2. Tombukt2

    Tombukt2 Senior Member

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    Durham NC
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    2009 Prius
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    Base
    So you did move the little transponder chip in the lower part of the case Little tiny black trapezoidal shape thing You got that in your new case because that's the thing that makes what you're talking about work not the green board with the battery that does all the stuff you have now but that little trapezoidal shaped transponder chip is what I have on my motorcycle built in my key and it only works when inserted It does nothing when I'm near the bike it's in my pocket stuck wherever until I insert it into the key slot and it gets close to the antenna than the red light stops flashing on the bike and everything comes to life My bike doesn't have a remote with buttons because there's no doors and what have you to unlock obviously so it sounds like to me you've just left out the transponder chip Do you have the old cases can you verify when I swapped out my cases and move the chip over SKS worked and regular transponder inserted worked I think at one point in another car in '05 I didn't move the transponder chip over and I think I had the same thing you had going on but then I took that car off the road so I never got to really mess with the transponder chip and open up the key to see what I had done or any of that because the car was no longer being used and it was being parted out but that's the only thing I can think of that would make good sense here.
     
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    May 12, 2018
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    Vehicle:
    2018 Prius c
    Model:
    Two
    There are two separate systems in use. You've taken care of the active radio system for remote unlocking.

    You forgot (or were unaware of the need) to move the passive RFID capsules from your old shells into your new shells.

    This post shows.
     
    Tombukt2 likes this.
  4. Tombukt2

    Tombukt2 Senior Member

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    I am awaiting this answer too