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My laptop is a Toshiba Satellite L500 and the screen has started going off after a second or 2 of use. For the brief time that the screen is on everything is clear and displays perfectly. Restarting the laptop or even just closing the screen and opening it again displays the screen for a second.

The laptop is otherwise working fine and I'm able to use it connecting to a TV through HDMI

What are the likely causes of this behaviour?


The Toshiba Diagnostics Tools reports a PASS on all tests.

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Have you checked the screen timeout settings (and changed them, even if they seem correct)? – Daniel R Hicks Apr 28 '13 at 13:13
(Might help a little to know what version of what OS you're running.) – Daniel R Hicks Apr 28 '13 at 13:14
Has it ever worked right? – Ƭᴇcʜιᴇ007 Apr 28 '13 at 14:45
did you try to run the toshiba hardware test. – Buscar웃 Apr 28 '13 at 16:55
@DanielRHicks Dual boots with Linux Mint 14 and Windows 7. Also tried with an Ubuntu live CD. Same results. – Fishcake Apr 28 '13 at 18:22
up vote 6 down vote accepted

This sounds to me as if the inverter is failing. When the screen darkens, can you still faintly see the image (you will need to look closely)?

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Over the years I have had to replace 2 of these. It cost me about 20 here in Toronto. – Xavierjazz Apr 28 '13 at 18:49
I can't see any faint image at all. But I'm starting to think it's the inverter. – Fishcake Apr 28 '13 at 19:42
Actually yes I can see a faint image, a lot fainter than I was expecting (it's barely visible at all). So would this backup the inverter failing? – Fishcake Apr 28 '13 at 21:18
Yes, that is a real sign. – Xavierjazz Apr 28 '13 at 23:56
Yep, sounds like the backlight has failed. – Daniel R Hicks Apr 29 '13 at 1:11

I would agree with @Xavierjazz that the issue is most likely the inverter. The screen inverter is a small electrical circuit board responsible for taking in DC current from the motherboard and converting it to AC current to power the LCD display.

My second guess would be that the backlight of your computer is failing. The backlight illuminates the liquid crystals to produce the display. The inverter does power the backlight, but the backlight can fail independently of the inverter. See for more information.

Since you mentioned that your laptop functions fine when hooked up to an external display, I would rule out the possibility of a defective motherboard or failing graphics card.

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Uh, the inverter powers the backlight. – Daniel R Hicks Apr 29 '13 at 1:12

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