Weird screen issue on M51S

Good afternoon,

I'm a regular visitor of the site and the forum, but now I had to register because this time I really need some help from you guys.

I have this M51S laptop with 2 problems. The most annoying one is the screen not working often on cold boot. Allow me to explain:

If I open the laptop and press the power button, in 90% of the cases the screen doesn't work. By this I mean completely nothing, no faintly readible BIOS screen or anything, just completely black. By pressing the power button on and off rapidly (causing a sort of reset-effect as if the laptop would have a reset button like a desktop) then the screen works almost every time.

To make it more weird; I can increase the chance of having a working screen from a regular cold boot by opening the laptop lid as far as it will let me (not forcing it). Then I have like a 50 to 60% succes rate of having a working screen from the first time.

Once the screen is working, it stays that way. It doesn't go black, doesn't fade, I can open and close the lid as many times as I want, it keeps working.
Also, I noticed that if the screen has been working for quite some time (1 hour+) and I turn off and on the laptop, it still works.

And last but not least; with a reboot (from Windows) the screen keeps working as well.

Any ideas ? The CCFL inverter ? Something else ?

 

It could just be a loose display cable, especially if you can get it to work with the lid in one direction.

Otherwise the inverter or CCFLs in the LCD would be your suspects.

 

All cables are tight and secure. I'm positive that cabling is 100% ok.

I think I'll try to replace the inverter, just wished anyone on the forum had any experience with these issues and would be able to confirm the solution ...

 

So you opened the lid bezel and flexed the cables and also reseated the connections on both ends (LCD and motherboard)?

The problem is pretty generic and an inverter is a $15 part, give it a shot as long as you are sure the LCD is CCFL backlit and not LED.

 

Correct.

I read about all sorts of problems on laptop screens going black but never encountered anything similar.

I agree on the CCFL inverter cost though, I'm gonna give that a try first.

 

A failing LVDS cable could prevent the backlight signal from ever reaching the display, or have skewed timing (same effect), which is why that is the first suspect when you talk about having the lid in a certain position.