Why does this cheap $4 key work in my Prius C?

Discussion in 'Prius c Main Forum' started by rosethornil, Feb 6, 2019.

  1. rosethornil

    rosethornil Junior Member

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    As a single woman, I wanted my friend to have a spare key to my car, in case I got locked out. Toyota *and* an independent locksmith wanted $200+ for the key plus programming.

    I got to thinking, I'm mainly worried about locking myself out, so I had a cheap key made at a local hardware store. It could open the doors, at any rate.

    Lo and behold, it starts the car up just fine.

    I thought these keys had chips in the head, as an anti-theft device.

    Can anyone offer some insight? And is this "spare" going to leave me stranded?

    Thanks for any explanations.

    [​IMG]
     
  2. fuzzy1

    fuzzy1 Senior Member

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    Was the original key with chip, outside the car during this test?
     
  3. benagi

    benagi Active Member

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    If the original key was with you when you did the test, it will start the car.
     
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  4. pdforever

    pdforever New Member

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    I think it depends on if the car came with an immobilizer or not. Mine is the "L" trim, so it doesn't have a push-button start, and the remote is similar to yours, but without that red button.

    When I got my Aqua (second-hand, auctioned from Japan), it came with just the one key. So, I went to the local keysmith to have a copy made. I wanted to at least have a key that'll let me unlock the car should I lock the keys inside. But hey, lo and behold, the basic key would not only unlock the car, but would also start it.

    I then did get another remote key made. The guy had to physically plug in a console to the car (from the inside), and register the key using it, so there is that.

    I am still going to get a physical lock for the car though.

    By the way, please black out the "teeth" of the keys in the pictures. I have heard of people using images to 3D print copies of keys.
     
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  5. rosethornil

    rosethornil Junior Member

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    I should have specified, the original TWO keys were placed in a faraday cage before attempting to use the new cheap key to start the car, so there is NO radio signal being transmitted. (I'm also an "extra" in amateur radio.)

    So - this has nothing to do with proximity to the original key fobs.
     
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  6. rosethornil

    rosethornil Junior Member

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    As to the 3D thing - those keys are in the shadows AND if someone wants to use those keys to make a 3D image and then come find me and steal my slightly used Prius C, I'd make national news! I'd go viral!

    Woo-hoo!
     
  7. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    How long was your test?

    In "regular" cars the engine would start and allow the car to drive under your described test conditions, but the immobilizer will cut the power to the fuel pump after 30-120 seconds. The car would stall out shortly after.

    I don't know what Toyota did for the immobilizer in the c, but if they borrowed off the shelf technology that same time limit would likely allow the car to get a bit further (due to electric drive potential) before the fuel cut immobilized the car.

    In a legal sense it allows the car to be stolen, yet be easily found and recovered. If the car simply didn't start, you might never know that somebody else had a working key to your car.

    Also consider the disruptive impact of a false negative read on the RFID key. Better to leave some slack in there so the legitimate key user doesn't get stranded. If the system checks several times over a minute, you have time to drive away from a randomly encountered RF emitter that might otherwise "trap" the car.
     
    #7 Leadfoot J. McCoalroller, Feb 7, 2019
    Last edited: Feb 7, 2019
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  8. rosethornil

    rosethornil Junior Member

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    During my test, I drove maybe 90 seconds total. See, I don't want to do a test if this is going to mess something up in the car (such as disabling the fuel pump).

    That's why I'm hoping that someone here has a definitive answer. :(

    I live alone, and I don't really have someone to come pick me up if I get stranded on Route 17, out by the hog farm. LOL.
     
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  9. Georgina Rudkus

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    Go to a Lowe's. Their Axxess key machine will detect if there is a in the key. My husband 2016 Nissan Versa has the buttons, but only opens and closes the door. The key part is totally conventional.
     
    #9 Georgina Rudkus, Feb 7, 2019
    Last edited: Feb 7, 2019
  10. sam spade 2

    sam spade 2 Senior Member

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    It does have to do with the trim level of your car.......and the fact that it does NOT have electronic theft protection on the ignition.
    Your test pretty much proves that.
     
  11. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I just had a peek at the online copy of the owners' manual, nothing useful. It's thoroughly dumbed down and doesn't even break out the difference between trims with smart keys and steel keys.

    From the 2019 OM:

    (emphasis mine)
     
  12. Georgina Rudkus

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    You don't have to buy any key from Lowe's. They will test your OEM key for free, to see if it has a chip in it.
     
  13. ETC(SS)

    ETC(SS) The other One Percenter.....

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    Congratulations on thinking about all of this ahead of time!
    You'd be amazed at how many posts contain some variation of the phrase: "I only have one keyfob."

    I'm guessing that you don't have the RFID immobilizer in your trim, or it's not enabled.

    Quite frankly, that's a FEATURE, not a fault.
    You may want to consider tie-wrapping another copy of the metal key somewhere on the exterior of your car, so that you do not have to wait for a rescue mission at oh-dark-thirty after you've had your purse stolen or you've locked yourself out of your car.
    We still have some G3 hatches in my company and the "smart key" technology has left more than one tech stranded outside an office that they've locked themselves out of, standing by a car that they cannot get into.

    Since I have to cover something like 12 counties, and since Murphy likes to hang out in bad places, late at night, in bad weather and/or where cell phones have weak batteries and signals....I use the same strategery with my work car that I do with my POVs....which includes having a keylet tie-wrapped to an exterior.....and yes.
    I had to use it.....once....at about 0200, in a somewhat disreputable downtown location.


    People don't plan to fail, but sometimes they do fail to plan.

    Good Luck!
    I envy you somewhat.
    I've often been a critic of the C-type, but it's proven to be THE MOST reliable of all of Toyota's cars (according to what you hear in this forum, at least.)
    The ability to upgrade from "smart key" to metal key might make a good, used C-type a more attractive commuter car for me if I have to start being a road warrior sometime in the future!

    PS
    I'd say something cool like 'seven-three' but I never got my ticket, lacking the commitment to deal with all of those dits and dahs.....
     
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  14. Georgina Rudkus

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    Likewise, I see little advantage to key chips and the Smart Key system. They are there to sell to the emotion of the buyer and has very little effective result as a theft deterrent, except against the dumbest thief. Electronics are high profit margin accessories for dealers and manufacturers. Electronics and tech can add 5-19k dollars to the price of a vehicle. That's has the same effect on the lenders and finance companies that relieve consumers of their future earnings.

    What's so hard about pushing the button on the remote?
     
  15. firstrival

    firstrival Member

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    Prius C One has no immobilizer. Any key with the correct bitting will start it.
     
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