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Key fob replaced and now you can't drive? Look here...

Discussion in 'Model S: User Interface' started by Matt_D, Apr 27, 2014.

  1. Matt_D

    Matt_D Model S P90D, Sig X

    Joined:
    Sep 3, 2012
    Messages:
    85
    Location:
    San Jose, CA
    Fellow Tesla fans,

    Thought I'd pass along a tip after a brief moment of panic last night.

    During my car's 24k service the tech replaced the key as he said it wasn't working properly. That's the good news. As is standard practice, you supply both keys when you come in for service.

    The bad news is that they were on the same keychain. Now you're probably wondering why that's a problem?

    The issue is that the "new" key works to unlock the doors if you depress the physical button on the key. But it doesn't work with either the proximity sensors in the car to open the doors NOR does it work to allow you to drive away. The older key seemed to work. Making matters worse, I had left the keys together as I was heading to a dinner before I got home and had both in my pocket. For some reason on the way back I decided to put one of the keys away in my bag, which is shielded. I placed the other in my pocket. Car doesn't open. I realized I could open the doors finally with the physical button and tried the other key and drove home.

    Upon getting home I called Ownership: we tried resetting the security module, swapping batteries between keys, and isolating if it was a proximity sensor on one side or the whole car. It turns out the key is defective in the most bizarre way; it acts as if the battery is dead yet works just fine with physical button presses to open the door. If your key does get into this failure state, holding it in the place documented in the manual for starting when the fob batter is dead will work here as well.

    I suspect the tech didn't notice it as they probably had both keys on one chain, so the handles auto-presented and they likely just tested the buttons on both keys. Caveat emptor: that won't catch all failure states, as you can see above. There's a workaround, but it was a little unsettling at first.

    Hope that's helpful for someone!
    Matt
     
  2. kendallpb

    kendallpb Model S: P 8061

    Joined:
    Oct 29, 2010
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    1,185
    Location:
    MD, USA
    "Standard practice"? I didn't, and wasn't told to. So my panic is from reading this. ;-) They did replace the fob I brought in, perhaps because the button on top was wearing through. It works fine (I kept using it), but out of paranoia, I just went out and checked the second key. It seems to work fine (at least, the auto-present worked). Whew! :-D
     
  3. Matt_D

    Matt_D Model S P90D, Sig X

    Joined:
    Sep 3, 2012
    Messages:
    85
    Location:
    San Jose, CA
    Right, they should replace the entire fob and reprogram both; sometimes they just swap the shell (or guts) but ideally both should be brought in when you have service.
     
  4. kendallpb

    kendallpb Model S: P 8061

    Joined:
    Oct 29, 2010
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    Location:
    MD, USA
    Aha, looking at the write-up, they replaced the casing.

    I'll try to remember that next year. This is my first car with a fob (and I don't believe my other half takes in both fobs for the Nissan Murano), so it's not intuitive. I didn't even know service/warranty would cover fob upkeep...kinda cool, they're expensive from what I remember reading in other threads.
     
  5. kevincwelch

    kevincwelch Active Member

    Joined:
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    2,015
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    Same thing happened to me during my annual service. I tried the usual stuff that was SOP. They didn't work. Ultimately, the replaced one needed reprogramming/replacement. I didn't ask, as it worked after I dropped off the car.
     

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