Can anyone detail LCD connections for me LCD repair

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I ahve purchased an Inspiron laptop on emaby and after 30 dyas its
starting to sow intermitent horizontal lines on the screen. These lines
look different each time and move around. They usually start when I
pick up and move the lap top. They can sometmes be "cured" by moving
the LCD screen back and forth, sometimes by pressing on the laptop area
above the heyboard, and sometimes they just go away.

But they come back.

I can run a monitor of the external video with no problems while the
horizontal lines are there.

The LCD screen stays bright all the time.

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There is nothing intrinsicly worng with the video on the laptop.
There is nothing wrong with the invertor.

There is a faulty connection somewhere either on the CPU board
the ribbon cable is bad
on the LCD board

Can someone clearly detail for me all the possible points of failure
and the liklihood of repair in each case.

I have no problem opening the case and replacin parts. I have replaced
ribbin cables before but I am concerned that it might be something more
serious like the conector connections on the logic board etc.

Any help appreciated



Re: Can anyone detail LCD connections for me LCD repair

Chasman wrote:
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It's unlikely that there's anything that you can fix.
IF the display cable goes, it likely takes the whole display out...or at
least a range of colors depending on the interface details.
For a few intermittent horizontal lines, it's probably the connection
between the display drivers and the glass.  You can't fix that.
Sometimes, depending on how it's constructed, you can put in some foam
to push the conductors where they contact the glass, but I haven't
seen one where they're accessible in a long time.

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Re: Can anyone detail LCD connections for me LCD repair

on the contrary, it's highly likely you can fix it.  it'll be an
electrical contact problem, most likely on either the LCD ribbon behind
the screen, or the connectors at either end.
on most dells (not done that one, but have done countless others) you'd
remove the screen surround, undo the screen and lean it out.  inspect
ribbon cable and carefully wiggle it whilst powered up.  if it makes a
difference, power down, battery out and clean contacts with isoprop.
if this doesn't do it, keyboard out and top plastics off, and find the
motherboard connector where the ribbon cable plugs in.  these work
loose - some dells screw them down, others don't.  again, remove and
clean with isoprop and see what happens.

Re: Can anyone detail LCD connections for me LCD repair

You have missed one of the more likely causes, the flat ribbon cables
that connect the LCD driver electronics (part of the panel) to the
actual cirucitry on the LCD glass.  Repair of these ribbons, although
possible in theory, is very, very specialized and is rarely done, and
may cost as much as a replacement panel bought right (not from Dell).

Also, less likely, but it could be the cable from the motherboard or
video card to the LCD panel.  These cables can be incredibly expensive
(sometimes over $100) and are hard to get.

Still less likely, the actual circuitry in the LCD panel drivers (part
of the panel, not the laptop).

Chasman wrote:
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