PBG4 Titanium Onyx - Screen black and sleeps when display moved slightly

Question

My PowerBook G4 has been going to sleep when I do any of the following:
1) Move the display — _every time_
2) Touch the lower row of keys on keyboard — sometimes
3) Bump the computer — _most of the time_
Sometimes when I try to wake it from sleep, the sleep light will stop "breathing," but the screen is still black, although I can see a very faint image. (...my forum research has told me this is the backlight turning off). A slight movement of the display will bring the backlight back on, but of course the PB goes to sleep.
I have reset the PMU and the PRAM.
I am hoping that the backlight problem is associated with the sleep problem, and one fix will solve them both, but I guess that goes without saying.
Would prefer to fix it myself rather that take it to a repair shop; I am fairly adept at repairs, but don't want to get in over my head.
Thanks Forum Gurus!

Answer 1

*+It WAS!+*
It was a classic case of the Orange Ribbon Cable Issue/Fix.
I was discouraged at first because the addendum to your article suggested that this did not apply to the *_550 MHz TiBook_*. But the ribbon looked the same as your pictures, and when I looked at the ribbon +with a loupe+, I could see where the insulation was worn away. I put tape everywhere I could fit it and the PB is working fine. I can totally move the display and pound on the keys with impunity. (I use the word "pound" figuratively, of course).
Now that I know how to remove the bottom case and the HD, I am definitely going to replace the HD.
Do you know what the best and most capacity HD I can install?
Thank you abundantly for your expertise and that very helpful website.
Cheers,
Paul