Solved! Cleaned laptop, boots but screen is black

[BlankScreenDead]

Hi,
My laptop was very dusty, so being really careful and following video instructions I took it apart, used compressed air and cleaned it, and put it back together. Now the screen is always black.
The model is a Toshiba Tecra S11.
I can login to windows (verified by sound). The computer realizes when the screen is closed and open (again, by sound).
All connections seem to be connected, and I was careful when putting it back together.
Tried Fn+F3 to increase brightness, and Fn+F5 to change output to no avail.

Any other ideas? Could I have messed up the backlight? (Barely touched the screen when I took it apart).

Any other info that might help?
Super appreciate quick replies, I am at wits end.
Regards.

 

[webworkings]

Try this...

1. Turn the laptop off (not sleep or hibernate but off).
2. Connect an external monitor to the laptop.
3. Turn on the external monitor.
4. Turn on the laptop.

NOTE: You may have to press an "external monitor" button. Could be the f4 button or a button with two monitors on it, for the external monitor to work.

If you can see fine on the external monitor, then your attached display, or the ribbon cable that connects it, are your problem.

If you can't see on the external monitor at all, or the problem occurs on the external monitor as well, then it is probably the graphics card/GPU that is the problem, which may require the motherboard be replaced.

 

[BlankScreenDead]

Thanks for your suggestion.
The external monitor is working fine, and I doubt I hurt the monitor. I have tried to double check the cables, but can't see anything out of place.
What is the ribbon cable, how do I locate it and see if thats the problem? I see two cables going from the screen, one by each hinge. They look Ok, and both pass into a tube-ish, cant see more. Have disassembled the laptop once more to try to find where it connects to the motherboard, but unable to find it
Any description would be helpful.

 

[webworkings]

It is so different inside every device, so I am not sure on the locations on yours. However were you to do a search online, I am sure you could find video(s) on how to replace a display for that device. Which then should show you the correct location for the cable(s).