Dell Screen not working

[kaycee73501]

If I plug my laptop in my screen will work fine I can even unplug my laptop after it is on and it works fine. If I try and turn it on just using the battery the screen is black and not woring the the laptop seems fine. This is a dell.

 

[robobob]

I noticed something similar with my dell laptop. If I boot with the lid closed the display never comes on! If I boot with the lid OPEN everything is fine on AC or Batt. ...can't seem to figure this out.