On Wed, 07 Oct 2009 16:20:12 -0700, Jeff Liebermann
wrote:
On Tue, 06 Oct 2009 18:19:51 -0500, Samantha
wrote:
I have a Dell E152FPc Flat screen Monitor 15" that goes black after
about a second after it is powered on. The Green power light stays on
and the color bar test pattern is there if you stick a flash light up to
it.
The LCD backlighting inverter has died. Everything else is probably
just fine. The really tiny inverters are tricky to repair as a
shorted turn on the xformer will usually blow up all the switching
FET's. However, this one is big and easy to work on. I still suggest
replacement. Tear apart the monitor and get the part number off the
LCD inverter. Then search eBay and Google for a scrap replacement.
One of these looks right:
http://www.lcdrepair.us/e152-e153fpc-inverter-power.html $40.
http://www.lcdrepair.us/e152-e153fpc-inverter-power-2.html $30
I have never had one of these apart and am not really sure what I am in
for. Just looking at it, I don't see any obvious way to take it apart.
There are some screws to take off the stand, but after that I am not
sure.
Anybody ever take one of these apart and fix it?
Bulging and leaking electrolytic caps are the most common problem.
Look at the board and you'll see about 8 electrolytic capacitors. If
they're even slighly bulging, they're bad. I'm lazy and replace them
all rather than trying to figure out which ones are blown. However,
with LCD inverters, the switching FET's are also commonly fried. If
replacing the caps doesn't work, I suggest just buying a replacement
board..
Would greatly appreciate any help.
Ummm.... you've heard of Google perhaps?
http://video.google.com/videosearch?hl=en&source=hp&q=lcd+monitor+repair#
http://www.lcd-monitor-repair.com
Lots more when searching for "LCD monitor repair".
Most of the monitor repair sites are nothiing more than an attempt to
sell an overpriced book 'How to repair LCD monitors'.
This specific problem is often referred to as the 'two seconds to
black' failure. A quick explanation of the operation of most
inverters, and the failu The inverter has a controller IC that
generates the signals that drive the transformers AND monitors the
voltage and current outputs of the inverter. Usually the start up
sequence consists of driving the CCFL backlights at full brightness
for several seconds, then beginning to monitor the output voltage
across and current through each CCFL. If the output voltage is too
high or too low, or if the current is too high, for any CCFL the
controller will shut down.
Possible causes of this problem include bad CCFLs, a shorted
transformer, breakdown of insulation in the wiring, or bad components
in the monitoring circuits. The Dell E152FPc and related models use
an unusual design in the inverter driver; a bad transistor can also
cause this problem. And yes, bad capacitors could also be
responsible.
This monitor also combines the inverter with the power supply. This
makes replacement difficult unless you can obtain a non-working
identical monitor inexpensively. Buying through eBay is usually
impractical. The cost of shipping is prohibitive.
Rather than spending the time and money to repair a 15" monitor in the
USA I usually suggest watching the local Craigslist and Freecycle
sites for somone giving away 'dead' LCD monitors. Currently I am
using a 23" wide screen monitor I purchased for $15, and repaired by
replacing ALL electrolytic caps at a cost of $7. My lates acquisition
was a 19" Dell which had a broken power button. Not only was it a
simple repair, the donor DELIVERED it!!!
One site I STRONGLY recommend is
www.badcaps.net/forum. They have
extensive discussions on repairing many LCD monitors, including this
one. Registration is required to post, but is free.
PlainBill