3 Replies Latest reply: Apr 10, 2011 8:18 PM by iVmichael
tvalente Level 1 Level 1
This just started happening. I am trying to use my LG LED TV as an external monitor. I plug my macbook in, and both displays come on (like normal). I then close the lid, and try to wake the macbook up with my external mouse or keyboard. It comes on for about 1-2 seconds, then the display goes black (no-input). Try it again, and again, same thing. I open the lid and it works fine with both monitors. What is the fix?

Also, would be nice to have an option to always send the signal to the external display.


MacBook Pro 5.1, Mac OS X (10.5.8)
  • iVmichael Level 6 Level 6
    Try doing a Parameter RAM reset - hold down command/option/p/r keys at start up and wait for three chimes before releasing the keys.

    I use Clamshell mode all the time (BenQ 24" LCD, Bluetooth keyboard, Magic Trackpad) but never turn the MBP off, just put it to sleep at night and then wake it in the morning by pressing the keyboard space bar or touching the trackpad.

  • nschulte69 Level 1 Level 1
    I had the same issue and then I realized it was because it was running off of the battery and not the power adapter. Once I plugged the computer in, worked like a charm. This is apparently how the new macbook pro operates with external displays.
  • iVmichael Level 6 Level 6
    Good point, clamshell mode has always required the MBP to be on MagSafe power though ...