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New "winter" fans, cigarette lighter 12 volts outlet never turns itself off

Discussion in 'Roadster: Technical' started by lmore, Nov 27, 2012.

  1. lmore

    lmore Member

    Nov 6, 2011
    Trondheim, Norway
    A few months ago Tesla Motors serviced my car and replaced the two PEM and motor fans with their latest version more suited for winter climate. They have worked well so far, the sound is different, but I don't find it annoying. The only thing that I think changed after the last service is that the cigarette lighter 12 volts outlet is ALWAYS on now. I think I remember that it turned itself off after parking the car for about five minutes. How should it work?

    I also still notice that if I leave the car parked for a day outside, the OVMS shows me that the battery has a temperature 6-10 degrees C above the ambient temperature. Is this normal? I read that if a battery cell has failed, resistors can replace the cell, can this be causing the temperature increase?
    The liquid-control of the battery seems to be constantly on since I can hear the sound from it.

    Recently I experienced three times that if I leave the battery on 25-35 % in standard mode and I leave it outside for 24 hours around freezing temperature, the battery capacity has dropped >10 %. It seems to settle on the low level. Anyone else seen the same?
    I can upload the log file if anyone is interested.
  2. cinergi

    cinergi Active Member

    Sep 17, 2010
    IIRC the 12V stays on if the pump is running. The pump will stay running if the ESS is warm enough. I don't remember getting it to the point where the pump would stay running for long especially when it's that cold out .. unless you're doing some high power charging and driving hard immediately afterwards or something...
    The pump consumes something like 100-150 watts so if it does stay running, you'll lose 3.6 kWh per day (assuming 150 watts) or about 7% SOC.
    Seeing actual ESS temps over that 24 hour period might help us diagnose.

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