Having problems with your Dell Latitude C840 Notebook ?

Screen takes several power up attempts to fire up

\015 I have a Dell Latitude C840 that i have to repeatedly press the power button on off on off sometimes maybe 20 times for the screen to fire up. Everything else seems to be getting good power as the hd and cd drive both spool up as well as all the indicator lights coming on. My best guess would be something faulty in the lcd inverter board, maybe bad caps? I don't know. I'd like an experts advice before tearing into it.\015\012\015\012Thanks!\015

Answers :

If you hear the hard drive spinning and you think Windows is working but you can't see an image then :-
You could have a defective screen - a defective inverter or a CCFL lamp or simply the video cable needs reseating. After reseating the video cable and the problem is still there then :-
To determine if you have a LCD screen or video card problem, read this and follow the instructions.

Defective CCFL backlight, it may have the following symptom:

\015\012
    \015\012
  • Screen flashs on red/pink and off. \015\012
  • Picture stays on in red and slowly be come normal. \015\012
  • Picture flickering with dim display or appear black. \015\012
  • Picture flickering on and off.
All these symptoms indicate that the LCD backlight lamp (CCFL Lamp) has reached the end of the life and all you need to do is replacing the CCFL lamp

Connect an external monitor to your laptop and power it up, if you see the normal Windows images then the video card and laptop is OK and the problem is definitely the backlight.

Dim image and/or dark display on the laptop's LCD screen indicates a faulty LCD backlight and it could be the inverter that supplies high voltage to the CCFL lamp or it is the CCLF lamp is nearly burnt out or burnt out, most likely this is the case.
The inverter can be replaced easily but the CCLF lamp is more time consuming and requires soldering skills.
Check out www.lcdparts.net for parts, repair service and DIY info.
Repair Help & Product Troubleshooting for Dell Latitude C840 Notebook

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