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Key FOB Vampire

Discussion in 'Model S: Battery & Charging' started by Cottonwood, Aug 19, 2013.

  1. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    As the manual warns, and I have experienced, leaving the key fob in or near the car can drain the battery quickly. The car stupidly keeps querying the key until it dies. At my house, this is a particular problem because my closet is directly over the garage, I leave the key in my pants or on the shelf in the closet, and the MS vampire sucks the juice out of the key fob battery. I have tried leaving the key fob in my office, but I should be able to just follow normal habits of emptying my pockets onto my closet shelf; I have learned to leave the spare key out of range. I have now replaced my third key fob battery in 10 months!

    First the work around: For those on Amazon Prime, Sony CR2032 Lithium 3V Batteries (10 for $4.91) will get you replacement batteries for under $0.50 each with free shipping. I leave some in the glove box and where I keep other batteries.

    Just like Tesla is working to drive a stake in the heart of the main battery vampire, they need to work on the key fob vampire. If the car is not moving for a while, most systems are shut down, and positive responses keep coming from key fob queries, then the MS should greatly reduce the query rate of the key. This can go back to a normal rate when something happens like a door is opened, the charge cable is removed, etc.

    Who knows, maybe the upgrades taming the main vampire in 5.0, will help tame the key fob vampire. Maybe the system that is doing the key fob querying will be shut down as part of getting rid of vampire loads. On the other hand, I hope that my closet key fob will not keep the main battery vampire awake.
     
  2. Doug_G

    Doug_G Lead Moderator

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    Drop your key into a metal box and close it. This is what is referred to as a "Faraday Cage".
     
  3. wycolo

    wycolo Active Member

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    > The car stupidly keeps querying the key until it dies. [Cottonwood]

    Are you monitoring the FOB's RF signal and seeing this activity? This would explain the reports of short battery life that butt-dialing does not explain. You could keep FOBs in metal canister or maybe even a steel file cabinet.

    Thanx for the battery source!
    --
     
  4. rdrcrmatt

    rdrcrmatt Member

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    All good points, but the thing people would complain about is the handles not auto-presenting because the system has slowed down its rate of querying the key at the time in which they walk up.
     
  5. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    That would only happen when the key was left in the car or very near the car. I would far rather have to double click the key fob or push the door handle, in the rare cases where the key was left very close to the car or in the car. To me that is a much better alternative than replacing key fob batteries every few months or having to lock my key up in a little shield box, a Faraday cage.
     
  6. vfx

    vfx Well-Known Member

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    Another reason for battery companies to love Tesla!
     

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