Dell Flat Panel Black Screen

[Guest]

Acquired a Dell screen E193FP. It works for a few seconds when the
image is fine then goes suddenly black. Power light is still on. Each
time I power off then on the same thing happens, image good then
black.
The PC/video card is fine with another screen.

In The Dark

 

[atwaterkent]

Cause of power going off: There is a bad 1000uF, 16V cap on the power supply board.



Solution: Replace cap. Radio Shack sells a 1000uF, 35V cap for $2. This will work.



Why did the cap go bad? The cap is too close to a heat sink and over heated.



What does this cap do? This cap sends a signal to an IC which keeps the monitor 'on' after the power switch is pushed. When the cap is weak, AC ripple voltage is applied to the IC and it sends a signal to shut the monitor off.



Opening the Monitor: These monitors are difficult to open.



The two plastic pieces snap together and must be pried apart with a flat screw driver.



After removing the stand, you need to insert a flat screw driver at the bottom of the screen where two slots are located. Then work the screw driver around until the two plastic pieces are separated.



Remove the cover plate and unscrew the push button circuit board.



Unplug the monitor cords from the driver board and remove the screen.



Unscrew the mounting screws from the power supply board and remove.



You will need to pinch the plastic support in the middle of the board to remove.



Cap Replacement:



Cap is located near a copper heat sink and the value will be on the side of the cap. It will be bulged up on the top. You will see burn marks on the board surrounding the cap. Unsolder the cap.



Install the new cap and solder. Make sure you connect + of the cap to + marked on the board.



Be careful not to solder across joints.



Keep leads long so you can bend the cap as far away from the heat sink as possible.



Reassemble monitor and turn on.



This should solve the problem.