Laptop screen will only come on if screen is tilted forward.

[g8kepr]

I'm working on a laptop (Toshiba Satellite C55-C5268) that has some strange screen issues. If the screen is tilted back in the normal position, it never lights up at all when turning on the laptop. I can't see POST or Windows loading, or anything. If I plug in an external screen, that works just fine and I can see that Windows has loaded.

If I tilt the screen forward, at about a 45 degree angle, and reboot, the screen comes right on...I can see POST, Windows loading, etc.. I thought it might be a loose cable connection, but once Windows is loaded, I can tilt the screen back and forth and all is fine. There is no flicker or anything. Then, if I try to reboot with the screen still tilted back, it's just black after the laptop reboots. I have to tilt it forward again, reboot, and all is fine again...and I can then tilt it back and use it normally.

This has me stumped, because a loose cable should show up every time I tilt it back. Once I do the boot with the screen forward, it's like nothing is wrong at all.

Any ideas?

 

[Your PCMD]

Heat. Had a similar instance happen on a Dell Inspiron. Tore it down to check the cable and all ribbon cabling and came up with nothing. From 90 degrees back, no image, but from a bit forward of 90 degrees to almost close, image galore. It was by sheer luck that I found the solution. Was working on a iPhone doing a screen replacement and had to use the heatgun to remove the glass, well the heat from the gun was hitting the Dell and low and behold, it came on. Damnest thing ever. So I took the bezel off and hit the whole thing with the heat gun. After that, worked like a charm and the client is still using it as far as I know. Could be worth a try. My only guess is that the glue they use to stick the board to the back of the screen was interfering somehow, heating it up just did something. Worth a shot. Good luck.

 

[g8kepr]

That's interesting... I never would have thought of heat possibly helping.

I also found that it has the same symptoms when waking from sleep mode.

If I close the lid to put it to sleep, then open the lid all the way, hit the power button, the screen is black. If I open it to about a 45 degree angle, hit the power button to wake it up, the screen comes right on and then I can tilt it all the way back.

This is really weird.

 

[g8kepr]

Are there any other ideas?

Heat didn't make a difference. The cabling is fine. There is one cable that runs from the LCD panel to the motherboard. The cable is in good shape and I unplugged and re-plugged in both ends. The only thing left is the LCD panel. I may just order one. It's just weird that it turns on at a certain angle and then works fine until it goes to sleep or is shut off.

 

[NETWizz]

I would run it with it half open then touch the cable, touch the motherboard connector etc. and see what causes it to flicker. Chances are although the cable looks fine it is probably broken internally.

It might be worth just buying the cable and trying it, but I cannot promise it will fix the issue.

 

[g8kepr]

I tried that and it doesn't flicker at all. Once the LCD powers on at a 45 degree angle, it works perfect...no flicker or anything.

 

[Your PCMD]

Heat didn't make a difference.

Sorry it didnt work. Worth a shot though. I dont know how much time you have in this project, but if its too much, then this would be better.

 

[kwest]

Replace the cable if that doesn't work replace the screen. Even if the cable looks fine it could have failed or been pinched.

 

[g8kepr]

It turned out to be a faulty cable. I still find it odd that once the screen was on, I could tilt it back and it would stay on for good. There was never any flickering either. It was definitely not the typical set of symptoms I'd ever seen. But, regardless, once I replaced the cable, everything functioned normally. Thanks for all of the ideas.

 

[kwest]

So what do I win