Hello Rosa Ann,
So if you:
- turn off the display with the switch on the back
- disconnect everything but the power cable
- turn the display back on again
Does the "Check Signal Cable" message on thescreen still looks dark?
You can press the 'menu' on the remote to see the menu and check colors/brightness...
If the menu is also dark please try Setup -> Reset -> Color Reset -> ok.
If this does not help then this is most likely a hardware problem .
Best regards, Peter