I have a 2009 white MacBook that doesn't seem to be waking from sleep properly. I close the lid at night to put it in sleep mode, and when I open it the next day, the display backlight doesn't turn on – I just get a black screen.
I know the computer itself is powered on because I can hear the fans running, and I know it's not in sleep mode because the sleep indicator light turns off when I open the lid. It's exactly as if you lowered the brightness to 0.
I tried adjusting the brightness, hitting all sorts of keys, etc. and nothing gets the display to come back – so I've resorted to holding the power key to force it off, then booting it back up.
Is there anything I can do, or is this a hardware failure? Surprised as the machine is only 3 years old (though it's my employer's, not mine!).
UPDATE: I have an external monitor hooked up to the MacBook, and when the MacBook's display fails to turn back on after waking from sleep, the external monitor also doesn't display anything – just the default "no signal" message that appears when the monitor is on but not plugged into a computer.
If this were an issue with the MacBook's internal display cable (as it seemed like it was), would that also prevent the external monitor from displaying anything?