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12v Battery

Discussion in 'Model S' started by FloridaGary, Feb 15, 2016.

  1. FloridaGary

    FloridaGary Member

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    Sep 27, 2015
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    Location:
    Orlando, FL.
    I received the error message today to replace the 12 v battery. I've only had my S for 6 weeks and thought this old problem was fixed with a software update after 4.0.
    I called my local Svc Center and the earliest they can see me is this Wednesday. Should I keep my fingers crossed commuting another 70 miles before they service it on Wed?

    Anyone else experiencing premature 12v battery failure?
     
  2. rxlawdude

    rxlawdude Member

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    Orange County, CA
    So much for the "we've improved the 12v battery" line. :-(
     
  3. Spyder14

    Spyder14 Member

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    Based on other threads, maybe put a trickle charge on it to see if a charge will keep it live for a while.
     
  4. Barry

    Barry Member

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    Colorado
    I had that problem about 6 weeks in, too. Took me a month to get a SC appt. I was nervous about it, but they assured me it was just an early warning and everything would be fine until then. They were right. Haven't had any battery issues since.
     
  5. Canuck

    Canuck Active Member

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    I've had no problems with my 12volt battery and it'll be two years in few weeks that I've owned the car.
     
  6. pedriscoll

    pedriscoll True Blue Tesla Fan

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    Indianapolis, Indiana
    I received this same warning about 4 months in to ownership. The service center told me that it was an early warning signal and that the battery should last several weeks before failing. They replaced it later that week. The servicing tech told me that the battery was just very slightly out of spec and could have lasted a good while.
     
  7. DillyBop

    DillyBop Member

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    Location:
    Middleburg, VA
    this happened to me too and my SC told me the same thing.

    FloridaGary, this is different than the catastrophic failure thing you've probably read about. you ARE okay to drive for a while, but it does need replacement eventually.
     
  8. Trailblazer

    Trailblazer Member

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    Dec 21, 2015
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    Location:
    Cornelius, NC
    I got the 12v battery warning on my dash after 8 weeks (2500 miles) with my Model S. I called the 800 number and they said that I should be fine driving it for several weeks if necessary. I looked around at the forum posts and saw several instances of people driving for hundreds of miles with the warning. So I drove it for several days - I was able to take it to the service center today and get it replaced - took exactly 1 hour. Seems strange that this problem is still occurring with cars with so few miles on them.
     
  9. FloridaGary

    FloridaGary Member

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    Location:
    Orlando, FL.
    Yes. I read some older threads where owners were getting towed. Our interstate in Orlando is undergoing a major 6 yr reconstruction and it's a mess driving 42 miles per day while traffic patterns shift. The thought of getting stranded in this mess has me hugging the outer lanes in case I have to pull over. In some stretches of our interstate there is no place to pull over.
     
  10. riceuguy

    riceuguy Member

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    Location:
    Austin, TX
    It's easy to panic about these things, but remember your previous car would have just had the battery die without warning you a couple of weeks in advance. The 12v battery weakness could be caused by anything (or nothing) -- a light left on, a bad battery, etc. However, the key is that there are no longer large batches of bad batteries failing repeatedly, and these warnings don't seem to be the false warnings that really meant your main battery (or drivetrain) was about to go out. So, essentially, don't panic...you should be ok!
     
  11. FloridaGary

    FloridaGary Member

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    I agree. I think it's great that we have an early warning system. This car has been nothing short of outstanding!
     
  12. CHG-ON

    CHG-ON Still in love after all these miles

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    16 months and 19K with no issues. Knock wood. But I expect that it will error out soon, based on all that I have read.
     
  13. NeverFollow

    NeverFollow Member

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    Does the error is always displayed or is showing only times to times?

    For peace of mind, I would perform a quick diagnostic using a digital voltmeter to see if there is a big change of voltage when turning on and off the "start" button, or turning the head lights, AC, or seat heating....

    Note: I'm not sure where to plug the voltmeter though.
    - I don't think that the battery is directly accessible without removing a cover.
    - Is there a Cigarette Lighter Socket Plug or any accessory plug?
    - Otherwise accessing the fuse box to an always connected wire would be another possibility.
    - Does the big display screen has a feature allowing to display directly the voltage of the 12v battery?
    - Also using the ODB-II diagnostic plug is another possibility http://www.teslarati.com/how-to-tap-constant-12v-power-tesla-model-s/

    A typical 12v battery should last about five years. If the 12v Tesla battery shows a low voltage, I assume that the battery get drained somewhere but the internal recharge system doesn't give enough juice to compensate during full load.

    If the error message is intermittent, I would assume that when the car is parked, like overnight, then the 12v battery get recharged.

    I think that from previous threads, replacing the battery was the remedy, but I would be more thinking that the re-charging system is more at fault that the 12v battery itself?
     
  14. WhiteStar

    WhiteStar Member

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    Probably easiest is to slide one or 2 old credit cards around the nosecone & pop it out. You’ll find the terminals there. Alternatively you could use a dongle like the CTEK Battery Sense. It’ll give you warning notifications via an app. You can also track SOC but not actual voltage.

    CTEK Battery Sense.jpg
     
  15. ThosEM

    ThosEM Space Weatherman

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    Annapolis, MD
    There really is a problem with the 12V battery, which has an expected lifetime, if all goes well, of only about a year (knock on wood! my second 12V is over a year old now). That's because it is put through far more cycles than the 12V batteries we are accustomed to in ICE vehicles, which are kept near full all the time. As we all know, any load whatsoever on the 12V battery when the ICE is turned off can quickly become a problem, as in overnight. The Tesla recharges the 12V from the main battery but does so as infrequently as possible, so with the car always alive electrically to some degree, it goes through a lot more cycles and deeper cycles than in an ICE car, which will quickly explore the limits of battery life. Instead of 5-7 years, we get about one year.

    I've heard no news of any innovative solution to this problem, but hope to...
     
  16. FloridaGary

    FloridaGary Member

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    Orlando, FL.
    My 12v battery was replaced yesterday and the tech said they will last 12-18 months. For what it's worth, they made the waiting very pleasant and I spoke with several people and also shown the Model X. So this is a shout-out to the Orlando Service Center. They were great to spend time with an the hour flew by.
     

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