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12v Battery Needs Service

Discussion in 'Model X: Battery & Charging' started by xkwizit, Jan 13, 2017.

  1. xkwizit

    xkwizit Member

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    IMG_0489.JPG Just past 9months and 13.5k miles, I guess a combination of cold weather, seat warmers, steering warmer, short trips, dash cam and the mifi was enough to kill the 12v battery :confused::eek:
     
  2. thimel

    thimel Member

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    Call your SC. They will replace it under warranty. This is common and has nothing to do with your electrical usage while using the car. It has everything to do with the vampire draw do electricity when you are not using the car. There are threads about this problem.
     
  3. xkwizit

    xkwizit Member

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    I thought that the vampire draw talked about in the forums is usually on the main battery that powers the motor not the 12v battery
     
  4. thimel

    thimel Member

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    What happens is the vampire draw is taken from the 12V battery which is periodically recharged from the traction battery. This cycles the 12V battery several times a day which wears it out until it dies.
     
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  5. K-MTG

    K-MTG Sunshade Captain of TMC

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    This makes me worried about my X, I have a 10-15 mile per day vampire drain on my X. And also have a always on dashcam + mifi like the @xkwizit. In addition, I have always connected checked and energy saver disabled.

    Are you gonna disconnect the dashcam + mifi before you take it in? I doubt that is the culprit but the SC might give it the blame.

    Can you still drive the car? Did you call the SC, hopefully they schedule you in ASAP. Please keep us posted
     
  6. xkwizit

    xkwizit Member

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    @thimel - That's counterintuitive. You probably know more than I have been able to dig up thus far. But it doesn't make design sense to me to draw from 12v battery and then charge it from the main battery. Plus the same issue should have happened with my S but its been 18months on that and the 12v battery is working fine. The differences between the two cars are what I mentioned in my original post.

    @K-MTG - Cap Sunshade ..I haven't called in yet due to the weekend but anyways the 12k service is also due. And yeah the car is working fine with that notification on the dash.

    And no I wasn't going to disconnect the dashcam+mifi setup they both get power from the source on the left side of the driver footwell. If they want to blame that, they will need to prove it. It cannot be 100% just those two- I think the seat heaters and type of usage matters. 12v batteries aren't expensive to replace. I don't expect them to make a stink about it at least this time. After all they gave me an extra sunshade last summer (not kidding :))
     
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  7. K-MTG

    K-MTG Sunshade Captain of TMC

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    Wow, an extra sunshade!!! I hope they don't blame the dash cam, but you could simply unplug the dashcam/mifi before taking it in? And leave all the wiring in place. Apparently some SC's unplug dashcam themselves.

    I didn't think this issue is widespread on the X as it is on the S. Is this the first report on the X?
     
  8. thimel

    thimel Member

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    My S needed a new battery after 9 months. YMMV. It takes significant power to run the D.C. To D.C. Converter and monitor it with all the computers. Hence they don't leave it running all the time. There are old threads with lots of information. Search is your friend.
     
  9. xkwizit

    xkwizit Member

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    @thimel - my apologies if it sounded like I was disputing your post..it's just that the whole concept of having a 12v battery seems insane and on top of it this 12v battery renders the car useless lol when you have a perfectly charged bigger battery
     
  10. MP3Mike

    MP3Mike Active Member

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    It is required for safety, you can't have 400V available all the time, so there are big contactors in the HV battery to cut power from the rest of the car. once the HV battery turns off you have to have power from somewhere to power the electronics and ask the HV battery to turn back on. Almost all EVs still have a 12V battery.
     
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  11. thimel

    thimel Member

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    No offense taken. I was just explaining why it is the way it is.
     

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