Intermittent fault - backlight on Sony LCD laptop

[RainyDay]

My Sony Vaio laptop is about 2 years old. About 3 times in that period, I've encountered a strange problem with (I think) the backlight. What happens is that when I boot up, the Sony Vaio screen appears as normal initially. When Windows XP kicks in, the Windows logo appears momentarily, and then the screen appears to black out. If I look really closely, I can just about see the screen image, but it seems as if the LCD backlight has cut out.

I don't think it is a hardware fault, as the backlight/screen operate normally during the very first few seconds of the booting sequence. If I hibernate, the normal progress indicators are fully visible. But it seems that when Windows takes over, the backlight goes off.

Physically closing over the laptop and reopening it seemed to correct the problem last night. I can't remember how I fixed it on previous occasions. I've googled and found a few other people with similar problems;

From http://www.hardwareanalysis.com/content/topic/5449/?o=240

Now, I have another problem with the computer and I was wondering if any of you have experienced anything similar with your sony laptop. My screen suddenly went black. The computer is working and I can see everything on a desktop monitor attached to it, but the screen itself is simply dead. I'd appreciate any advise or information in regards to this problem. I have tried to call sony to find out more and i was put on hold three times for about 20 minutes. What a laugh...

From http://www.hardwareanalysis.com/content/topic/11258/?o=20

I have an VAIO FX220, I bought it in August 2001. Two weeks ago the screen started "flickering" after a day of this the entire screen went VERY dim, almost pitch black. If i look at it at an angle i can barely see what is on the screen. It displays fine on an external CRT, so I believe it is either a backlight or inverter. Not sure though. Someone said that since the entire screen was black likely it was the inverter, that is if this model has 2 backlights: top and bottom. This is ridiculous, it sounds like a manufacturing flaw, I have never heard of a laptop malfunctioning so early, I guess I have been fortunate though with 2+ years. I will never buy another Sony laptop again, that is for sure.

From

My old Sony Vaio PCG-GRX3P (hell expensive when I bought it) has for the last few months experienced an intermittently faulty LCD backlight.

I'm wondering what my options are - I'm still under 3 year extended warranty on the machine, but it may be difficult to get a repair given the intermittent nature of the problem. No doubt, if I don't get thing sorted now, it will fail permanently as soon as the warranty expires.

Any suggestions?

 

[ClubMan]

Try booting off a "live" CD GNU/Linux distribution such as Kanotix, Knoppix, Ubuntu etc. If the screen behaves OK then it may well be a Windows specific issue and you can then look at checking what sort of configuration settings may need to be tweaked. If it misbehaves under GNU/Linux too then it certainly suggests a hardware issue.

 

[RainyDay]

I'm not sure if this will help me much given the intermittent nature of the fault. For example, it booted fine for me under Windows this morning, but I'm worried that there is still something 'under the hood' ready to fail.

 

[ClubMan]

I thought you said that it was predictable?

What happens is that when I boot up, the Sony Vaio screen appears as normal initially. When Windows XP kicks in, the Windows logo appears momentarily, and then the screen appears to black out. If I look really closely, I can just about see the screen image, but it seems as if the LCD backlight has cut out.

Whatever about it not helping much it's one useful approach to a process of elimination in diagnosing the cause of the problem.

 

[RainyDay]

Nope - Definitely not predictable - I did mention that it was intermittent and that it happened 3 times in the 2 years since I owned the machine. So I just don't see how the Linux booting would help diagnose one way or other.

 

[ClubMan]

What happens is that when I boot up, the Sony Vaio screen appears as normal initially. When Windows XP kicks in, the Windows logo appears momentarily, and then sometimes the screen appears to black out. If I look really closely, I can just about see the screen image, but it seems as if the LCD backlight has cut out.

Is that more accurate? I personally would still try the Linux boot just to see if the same problem ever arises under another OS. But feel free to ignore the suggestion if you prefer.

 

[RainyDay]

To be honest, I'm pretty comfortable that the original post was accurate, given that it included 'intermittent' in the thread title and included the following context which you omitted from your quote;

laptop is about 2 years old. About 3 times in that period, I've encountered a strange problem with (I think) the backlight. What happens is that when I boot up....

Given that the fault has occured 3 times in 2 years, I don't think that the non-appearance of the fault under Linux would help in the diagnosis.

But thanks for your efforts.

 

[ClubMan]

I don't think it is a hardware fault

...

But it seems that when Windows takes over, the backlight goes off.

By your own analysis it soulds like trying another OS would be useful.

 

[RainyDay]

Yes, but given that 99.99% of the times that Windows takes over, nothing untoward happens - I don't think I can draw any sensible conclusion from a few test boots under Linux.

 

[ClubMan]

Yes, but given that 99.99% of the times that Windows takes over, nothing untoward happens

Assuming you boot it once a day every day for the almost two years that you own it then it's actually a non failure rate of ((2 * 365) - 3) / (2 * 365) = 99.59%.