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Car Charging Setting Not Sticking

Discussion in 'Model S: Battery & Charging' started by theslimshadyist, Jan 4, 2017.

  1. theslimshadyist

    theslimshadyist NashVegas!

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    Hey guys, I'm running 2.50.180 and noticed that my car was only charging at 30 amps so I went into the charging setting under controls and changed it to 40 amps. I then went for a drive and when I returned home and plugged in my charger, the car reverted back to 30 amps. FWIW, my NEMA 14-50 is 50 amps.

    Anyone else seeing this behavior?
     
  2. thimel

    thimel Member

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    This can happen if your car detects too much voltage drop when it starts charging. This can indicate a bad wiring connection. It reduces the current to prevent a possible fire. See if the problem only occurs on the one outlet. If so, have an electrician check your wiring.
     
  3. BerTX

    BerTX Active Member

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    I haven't played with this much, but of course the car remembers the charge rate you set for a particular location. I assume if you re-set it to a different level, then it remembers that rate. Maybe you set a lower level at some point in that location and it is remembering it? Maybe a bug in the code BUT for safety reasons you should get the outlet checked.first. Something as simple as a loose connection can cause a drop.

    I guess you could try setting it to a lower level at a different charge location and see if it does the same thing.
     
  4. theslimshadyist

    theslimshadyist NashVegas!

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    This wouldn't be the case for me because I changed it to 40 amps, ran some errands and when I returned home, I went into "charging" and it moved back to 30 amps. All of these events occurred before I even plugged in the charger.
     
  5. TexasEV

    TexasEV Well-Known Member

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    I still think the most likely explanation is it remembered the decrease to 30A at that location earlier. Search this forum for 40A dropping to 30A for lots of posts about possible causes.
     
    • Informative x 1
  6. theslimshadyist

    theslimshadyist NashVegas!

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    Seems to be holding now, as mentioned above I believe the car was remembering the charging location when it may have been previously set to 30a. Any idea how to clear the "saved" charging locations that are saved into my car? I went into the Nav app and I can see recent destination history but nothing about saved charging location settings.
     
  7. Barry

    Barry Member

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    Another possibility is there was a power glitch. The car will drop the amperage by 25% (in this case 10A) if there's some glitch, such as too much of a voltage drop as it ramps up to 40A.
     
  8. mknox

    mknox Well-Known Member

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