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USB port disabled after too much power.

I can't enable 2 USB ports. I attached a Asus Wi-Cast and it shutdown the computer and disabled 2 USB ports on the back of Mac Pro.


MacPro Mountain Lion

(only devices are mouse/keyboard. Also they wont work on the 2/3 usb ports on back)

  • I reset PRAM
  • I unplugged and held down power button.
  • Open up Mac and held down the buttons on logic board.
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What makes you think they are disabled as opposed to, perhaps, shorted (busted) for the power overload? – thornomad Dec 18 '12 at 18:37
Either the USB device you have connected is actually drawing too much power, or the sensor to detect too much power has failed. A process of elimination should guide you to which situation is the case. – bmike Dec 18 '12 at 19:03

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