Question about Compaq Presario CQ56-115DX Laptop

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Backlight won't turn on

My backlight won't fully turn on. it turned just fine last light, then i turned it all the way down. This morning, it won't light back up. there's a red light by where the charger plugs back in, the light is usually white. Neither the light button nor going to the data option to manually turn it up work. When i manually try, it slides to say it's on but it won't stay on.

Posted by Austin Bridges on


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  • 95 Answers

Your laptop probably in power saving mode, it is a preset to makes battery last longer. your power adapter might not being detected shown by red light, try to plug it firmly or use other power adapter if available

Posted on Dec 02, 2013


5 Related Answers


andrew pester

  • 2961 Answers

SOURCE: backlight fading

you can adjust the brightness by pressing the Fn button along with the *left/*right button on the right side of the keyboard

Posted on Oct 22, 2007



  • 101 Answers

SOURCE: my lcd backlight has burned out

There are four options. One is to replace the entire LCD Panel. Not cost effective but probably the easiest. Two is to replace the flourescent tube, but this requires unmounting the panel from the laptop, disassembling it, desoldering and soldering the old/new tubes, reassembly and remounting. The time and hassle is not worth the amount spent on a new LCD (besides, the flourescents are very fragile and break easily, plus they are made with lead so you must wear gloves for the replacement procedure). Three is that you can use an external monitor, so long as you have no reason to move the laptop. Fourth is buy a new machine.

I would probably look on eBay for a known good used panel or even a dead system on the same brand/model which has a good LCD and then change the panel myself. It is not that hard, especially if you find the right service manual.

But how do you know it is the backlight? It might also be a bad inverter. An inverter is about $30 where a new LCD would be $150 or more, and even a used one might run $75. Best to try to find a non-working used system with no video problems, or maybe even a complete replacement top on eBay so you have all the parts you might need.

Posted on Dec 30, 2008


  • 41 Answers

SOURCE: Compaq R3000 laptop screen went black

Give this a try -

1. Remove all USB devices such as printers, mp3 players etc etc.
2. Remove the power-cable and the battery
3. Press and hold the power button for 30 seconds
4. Put the power-cable back in but not the battery and none the USB devices.
5. Turn the computer on

Let me know if it doesnt work.

Posted on Jan 20, 2009


  • 3 Answers

SOURCE: My compaq 572US was on sleep and now when I hit

its a defective graphics card...there is a class action lawsuit for this model and many others. search nvidia class action lawsuit. you can get it repaired or replaced with the settlement terms. I have same laptop, same problem!

Posted on Sep 29, 2010

Margaret Glanville

  • 1542 Answers

SOURCE: when i turn on the


I know this may sound silly but have you tried starting it up with the power adapter switched on and plugged in

Posted on Nov 18, 2010

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