Thinkpad 600E LCD is not working

[Helixal]

I recently had a problem with a very dim display. It could temporarily be
revived by turning the display on and off. I then replaced the ccfl
backlight. This did not solve the problem. I still had the dim display.
But in diagnosing the problem further, I did not secure the LCD panel in the
cover and it fell onto the keyboard. It didn't fall far but the dispaly
went black (not even dim as before) I noticed that the ribbon cable was cut
in one place due to the fall. So I got a used ribbon cable and while I was
at it a used inverter. Replacing the inverter and the ribbon cable have not
improved the problem. The screen is still black and the backlight is not
lit. I have connected the laptop to another display through the external
jack and it works fine.

Any suggestions?

1) Is the problem confined to the LCD display?

2) Can I fix the current LCD display in some way?

3) Will replacing the LCD panel fix the problem?

Thanks

[sktn77a]

If you hold the computer in a bright light, can you see an image on the screen? If so, it could still be your backlight. If not, it could be anything from the cable, to the inverter, to the GPU/motherboard.

[Helixal]

You can't see anything in bright light. The screen is totally black. You cannot see desktop icons even faintly. It's not the backlight since I put in a new one and it worked. As I said I replaced the inverter. My concern is whether it can be something on the motherboard. I don't think so since the computer works fine with and external monitor. But I am not sure.