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master key stolen-reflash immobilizer ECU?

Discussion in 'Generation 1 Prius Discussion' started by depriusoto, Nov 27, 2014.

  1. depriusoto

    depriusoto Member

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    My niece's apartment was broken into, she was assaulted and her purse with the Prius master key, remote and driver's license were stolen. I have a back up Master key and remote which I gave to her. We are worried that she may have been stalked and the criminal may try to steal her 2002.
    I've read through some of the posts about lost keys, etc and can do the 'chicken dance' to program new keys and remotes. My specific question is this:
    Does the immobilizer ECU only transmit one signal. If yes, I believe this means that the stolen key can still work even if I program new master key(s) and remotes. Am I correct?
    If this is the case, I'm assuming that we will need to reflash or replace the immobilizer ECU and get a new master key and then I can reprogram subsequent keys and remotes.
    If, on the other hand, the immobilizer transmits more than one signal, can a locksmith or Toyota dealer create a new master key using a different signal. I believe this would render the stolen key useless.

    We're checking into whether her renter's insurance (State Farm) will cover the cost of replacing the key and remote and if necessary, the immobilizer ECU.

    Ed K
     
  2. ChapmanF

    ChapmanF Senior Member

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    Every key that came with the car* has its own code. There are several 'chicken dances' you will find in volume 1 of the service manual, and one of them is the 'forget all keys except this one' dance. You'll want to do that dance right away using the master key that you have. That will render the stolen key useless to start the car (it will still open the doors and trunk and unlock the steering, though).

    The remotes are programmed separately, there is a separate dance to forget the stolen remote.

    You don't need to spend any money on ECU replacement or flashing.

    You can buy a suitable key on eBay (about $17 last time I bought one) that can be cut to match your key. It will have its own code and you can do the chicken dance in the manual to register it with the car.

    There are also, slightly more expensive, keys with writable codes. Instead of the key coming with its own distinct code and needing to be registered with the car, one of those keys can be stuck into a cloning tool with your existing key, and comes out having the same code. (Of course then, if one of those keys gets stolen, you can't just forget it without forgetting the other one too.) That's why I put the (*) on "every key that came with the car." If any of your keys weren't originals, it might be possible some of them are clones.

    You can buy and register a new remote fob too, but they cost more than the keys.

    -Chap
     
  3. depriusoto

    depriusoto Member

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    thanks for the good news!
     
  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    FYI, my understanding is the Prius 'remembers' a maximum of three keys and three fobs.

    Bob Wilson