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UMC Button Interrupts Charging Even When Locked

Discussion in 'Model S: Battery & Charging' started by iffatall, Mar 17, 2016.

  1. iffatall

    iffatall Member

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    I always thought pressing the button on the UMC while the car is locked (and charging) only re-ignites the charging LEDs momentarily, without affecting the charging process in any way whatsoever. I am even almost certain I tested this a while back.

    But recently, I noticed that pressing the button actually interrupts charging. I noticed this while charging at home, using the 14-50 plug. It was early morning, and the car had been charging overnight. I went to the car (no key fob), and just pressed the button. The LEDs turned on, green, and switched to blue immediately. I got a notification on my phone that charging was interrupted. Since I had scheduled charging setup, charging did not resume automatically. I then had to force start charging from the app - all this while, the car was locked, and the UMC remained locked to the charging port.

    Can someone check if they see the same behavior? (I want to confirm if this is a s/w change or a defect in my car alone). This is not desired behavior, is it?
     
  2. Lloyd

    Lloyd Active Member

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    It has always been this way. By pressing the button, the car thinks you need to unplug, and stops to flow of electrons to prevent them from jumping to an unintended location! :eek:
     
  3. iffatall

    iffatall Member

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    Even if the car is locked? Doesn't this allow someone to interrupt your charging when you are not around?
     
  4. Lloyd

    Lloyd Active Member

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    They can interrupt, but they cant disconnect. It has always been that way.

    That said, I have caught some unscrupulous owners in Gilroy interrupting my charge to become primary in the charging pair. I agree, when the car is locked and charging you should not be able to interrupt and uplug until the car is unlocked.
     
  5. iffatall

    iffatall Member

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    Wow, I can't believe I have had the wrong idea for this long. I don't see why it has to be this way.

    Thanks for clarifying.
     
  6. iffatall

    iffatall Member

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    I hope it isn't widely known :p
     
  7. Ingineer

    Ingineer Electrical Engineer

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    The button changes the proximity signal telling the car's charger to immediately stop pulling power so that if the plug is removed there will be no arcing that could damage the connector.

    It's always been this way, and it's the same on other EV's equipped with a J1772 charging port as well.
     
    • Informative x 1

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