Hot black corner in laptop screen

24 Aug 2009
Posted by Laptop Junction

Quite a while after replacing the LCD screen inverter the LCD screen of the Dell Latitude D610 started to have problems. After several weeks the screen died with tell tale signs of CCFL back-light tube malfunction. The screen had been used to the extreme, here the story of a dying CCFL tube.
 

Black corner - hot spot in screen

For several weeks the Dell Latitude D610 occasionally had screen flicker, particular during start-up and and maximum screen intensity. A high pitched hissing noise came from the bottom end of the screen. Both phenomena's would usually go away after a while but always came back, sometimes several times a day. If that wasn't enough a black spot started to appear in the bottom left corner of the screen. The screen became very hot in that particular corner, too hot to touch. It seemed the screen was dying.
 

hot black spot in the corner of the screen
Hot black screen corner in DELL laptop


The next day the D610 started with a black screen, although the D610 worked perfectly on an external monitor. Was it  the screen inverter again or was the CCFL tube in the WXGA+ screen dead? A quick test with a screen inverter from a cannibalized D610 proved the worst - the CCFL tube had died. After-wards the CCFL tube lit up several times for just a few minutes or seconds. After a day it didn't return to life. 
 

CCFL tube broken

Opening the DELL Latitude D610 LCD screen reveals a broken CCFL tube. One end of the tube got extremely hot melting the soldering. The wire immediately fell off after disassembly.
 

 NOTE: The CCFL right end sits at the left bottom corner of the LCD screen.

Broken CCFL tube in a DELL D610 Latitude LCD screen

 In the coming days the CCFL tube will be replaced by a new one. 
 

What to do with a dead inverter or CCFL tube?

From a cost point of view there are a few DIY options with cost estimates for a DELL Latitude D610
 

  1. DIY Repairing
    1. 20 - 30 US$ - A dead inverter can be easily replaced within 30 minutes.
    2. 30 - 50 US$ - A dead CCFL tube is a delicate repair job and takes a few hours.
       
  2. DIY Replacing
    1. 60 - 150 US$ Replace the screen - 1400 × 1050 SXGA+  upgrade is possible.
    2. 200 - 300 US$ Replace the whole system - sell or keep the parts
       
  3. Limping along
    1. Connect external monitor - given there is one available.
    2. Remote login through XP Remote Desktop - assuming remote access is configured.
       

With a dead CCFL tube i chose to buy a 2nd hand D610 upgrading to fastest model available, a 2.1 Ghz Pentium M. The broken screen was set aside for later repair.

The harddisk with the Windows XP installation of the D610 with the broken CCFL tube can be easily migrated without re-installation to the new one.

As a precaution the disk was copied using a drive-imaging program. The backup was restored on a new harddisk. The old disk was set aside as a operational backup.