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    Abrupt Intermittent Restart on T420?

    Discussion in 'Lenovo' started by Faustus, Dec 25, 2011.

  1. Faustus

    Faustus Notebook Enthusiast

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    Hey, something odd has been happening for the last month. My T420 screen goes black and restarts. So far this has been happening only when charged via outlet.

    Really have no other information. Does this sound fimiliar?
     
    Faustus, Dec 25, 2011
    #1
  2. PatchySan

    PatchySan Om Noms Kit Kat

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    Occasionally when I plug the power back in to my T420 the LCD backlight goes off suddenly, its only when I close the lid and bring it back up it resumes back to normal again but it doesn't restart though.

    If you haven't done so, try updating the BIOS and the Power Manager app to see if it help matters.
     
    PatchySan, Dec 25, 2011
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  3. Faustus

    Faustus Notebook Enthusiast

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    That happens as well but the problem that I am describing is a complete restart. I hear a slight, very short click sound and then the computer restarts.

    Thanks,
    Faustus.
     
    Faustus, Dec 25, 2011
    #3
  4. Tsunade_Hime

    Tsunade_Hime such bacon. wow

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    Perhaps you have a short? I would;

    - Test your AC adapter with a multimeter
    - Use a known good 65 or 90 watt Lenovo AC adapater
    - Hold down the power button for 30 seconds 2-3 times

    Otherwise you might have to RMA/call up Lenovo for service..
     
    Tsunade_Hime, Dec 25, 2011
    #4