Question about Dell Latitude D505 Notebook

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Backlight of LCD turns off

My Dell Latitude D505 works fine other than the backlight turns off after a few seconds after de Dell logo.

If I press the little switch (lid close) the backlight turns on for a few seconds then it turns off again.

After several tests I have concluded that the backlight lamp works but something else makes it turn off.

Is there a timer adjustment?
Is there a part that controls the time it stays on?

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Re: Backlight of LCD turns off

For latitude systems they have this ambient light sensor. it basically adjusts the brightness of the screen depening on room lighting. try to go to bios by hitting F2 on the dell logo. go to video and try to look for ambient light sensor. however, im not sure if your computer has that feature I have a second option for you though. based on the troubleshooting you've done, it seems that the video back lighting is affected by movement. it would be a good try to reseat the LCD cable. you can use this link to guide you in fixing the computer :
all you need to do is to take out the keyboard with 2 screw holding it in place. the LCD cable should then be accessible. it a thick cable that coming out of the Left hinge.

Hope this helps.


Posted on Dec 25, 2007

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Suggest you replace the Inverter. A Backlight goes out all at once.
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[ An LCD screen cannot produce enough light by itself.
A Backlight is used to supply the needed extra lighting.
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Dell Support > Latitude D600 Notebook PC > Service Manual

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Display is very dark and can barely be viewed. Brightness controls don't do anything. Any suggestions? It is a Dell latitude 505.

Sounds like the back light has gone.
You may be lucky and you just have a loose connection, its worth taking the front off the screen surround and re-seating all conectors.
If it is the backlight, you can get a replacement quite cheap (£10)
I found this site

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