LCD NEC 1530V Blank bottom third

[paintmadman]

LCD repair experts,
I need your help. I have a flat panel display NEC Multisync 1530V
that works great except the bottom third is blank. I took it apart
and fiddled with the ribbon cable and made the entire screen go blank
white but it still had a dark line separating the bottom third from
the rest. I disconnected and turned off the monitor and reconnected
it to the video card and the upper 2/3 came back. the bottom third is
still blank (it's backlit but blank). Other monitors work just fine
on this system and the NEC has the problem whether it's connected to a
PC or not.

There appears to be some tiny resistors or diodes connected to the
ribbon cable, about 12 of them on the left side. What kind of voltage
or signal should I look for there? Is the screen controlled in thirds
by some semiconductor? There are two pairs of wires on the right
side, They seem to be involved with the backlighting function.

My ancient knowledge of displays is all based on CRT's so I'm afraid I
don't know where to start.

Any help will be appreciated. Thanks in advance.

Dennis

 

[Jerry G.]

The signal from the controller should be scoped out to see if there is feed
to the LCD matrixing. Beyond this you cannot fix this without subing the
boards. Board level repair is not even done by the manufacture service
reps. They do board swapping to service. The panel with its back plane
board is changed as a complete module.

The monitor may not be worth to service if it is out of warranty. NEC, like
the others, will not sell any parts or service information to non NEC
authorized service people.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"paintmadman" <paintmadman@comcast.net> wrote in message
news:94ee7a97.0401080102.4ad5e5cd@posting.google.com...
LCD repair experts,
I need your help. I have a flat panel display NEC Multisync 1530V
that works great except the bottom third is blank. I took it apart
and fiddled with the ribbon cable and made the entire screen go blank
white but it still had a dark line separating the bottom third from
the rest. I disconnected and turned off the monitor and reconnected
it to the video card and the upper 2/3 came back. the bottom third is
still blank (it's backlit but blank). Other monitors work just fine
on this system and the NEC has the problem whether it's connected to a
PC or not.

There appears to be some tiny resistors or diodes connected to the
ribbon cable, about 12 of them on the left side. What kind of voltage
or signal should I look for there? Is the screen controlled in thirds
by some semiconductor? There are two pairs of wires on the right
side, They seem to be involved with the backlighting function.

My ancient knowledge of displays is all based on CRT's so I'm afraid I
don't know where to start.

Any help will be appreciated. Thanks in advance.

Dennis