LCD troubles..works with monitor...

[S911houston]

Hi I have been trying to get my Dell inspiron 2500 to show something anything on the lcd but to no avail...it works with an external monitor.
I have tried to reset the flex cable but nothing...

When I start it up the screen is jetblack! then it flcks to a grayish blue then at the point that windows would be on the screen it show a light gray with vertical stripes.
This is a used laptop no warenty! So I have to fix this myself..Any glues what to do?

:rolleyes:

[TallCool1]

When I start it up the screen is jetblack! then it flcks to a grayish blue then at the point that windows would be on the screen it show a light gray with vertical stripes.

Does it have a floppy? Can you boot to DOS? If so, can you see a text screen? What version of Windows are you running? The prognosis is not favorable, but all is not lost.

[S911houston]

Hi the laptop has a floppy(but why is that important) ..Its boots up to windows with an external monitor..(the unit works fine)There is nothing on the LCD...it start out black then goes to light greenish white then when windows is up and ready the screen goes gray...I was thinking flex cable need to be replaced?....

[TallCool1]

Hi the laptop has a floppy(but why is that important).

I was trying to see ifany text showed at boot-up. It's clear that your backlight is coming on, but nothing else.

It's possible that the flex-cable is bad, but unless it's kinked or obviously cut, that's extremely unlikely. What happens much more often is that the unit is dropped, the liquid crystal panel itself shifts in relation to its contact pads and loses its electrical connection.

The LC panel connects to the electronics via an elastomeric (rubber-like) contact assembly. It's a series of fine, parallel wires molded into a block -- like encasing a comb in rubber. The wires are insulated from each other, but exposed on the contact ends between the panel and the driver printed-circuit board. It doesn't take a lot of stress to dislodge things.

I haven't had much luck fixing this kind of problem. It usually requires a special jig or fixture to ensure proper alignment of all the elements.

[S911houston]

HI I was wondering if it is posible to use a different LCD in my laptop? or do I need the exact LCD

[TallCool1]

HI I was wondering if it is posible to use a different LCD in my laptop? or do I need the exact LCD

Exact replacements only, unfortunately, usually matched by brand and series. It may cost you more than the used machine itself.

[S911houston]

Thanks..I was able to get two P/N 7F090 and 8F086. How could I fine out what LCD are they?...and Is the away to fined out if another laptop uses the same LCD?...

[whipaway]

try the user forums on Dell's website, the guys there can cross-reference the part#s to which models they fit.

[S911houston]

Thanks for the replay ! will do!

[S911houston]

[QUOTE=TallCool1]I was trying to see if any text showed at boot-up. It's clear that your backlight is coming on, but nothing else.

It's possible that the flex-cable is bad, but unless it's kinked or

Hi.I was able to get another LCD. This one works but has a Red stripe from top to bottom...is there anything I can do to fix it?...oh yea it also has a couple of light circular spots any I deas?

[JohnG139]

Hi.
I have the same problem with my latitude LM.

QUESTION FOR TALLCOOL1

In the latitude, the LCD

[JohnG139]

sorry - hit the

In the latitude, the LCD screen is secured by 4 screws - immoveable! The flex cable has sockets on both ends that engage opposite sockets on the MOBO and LCD. (The branch that attaches to the inverter board has metallic contacts on the end which slide into a ziff connector)

The elastomeric (rubber-like) contact assembly you refer to, is that the end that plugs into the MOBO?

jOHN

[TallCool1]

The elastomeric (rubber-like) contact assembly you refer to, is that the end that plugs into the MOBO?

No, it is the connector between the driver electronics and the LCD glass itself,inside the display assembly. It's a sandwich, with the LCD substrate (glass with transistors and conductors) as one "slice of bread", the backing board (with the signal contacts) as the other "slice", and the contacts between them.

Another way of looking at this is to think of the contact assemblies as a gasket on the underside of the LCD glass between the substrate and the backing board. That's why an alignment jig is usually needed -- everything must be set up just right for it all to work -- and why it's often so easy to knock out of alignment.

[JohnG139]

Ok,
I gather from your description that the mis-alignment is in the LCD screen module itself, not the socket in it into which the flex cable plugs.
In any case, my system was never dropped, or received any significant shocks.
Since it worked before I fried my MOBO flashing BIOS A05 we can assume that the problem very likely does not exist with the LCD screen itself, therefore only the cable, or ??
Could there still be a motherboard problem? The board I bought was supposedley refurbished, and came in a DELL box, so SHOULD be OK.
The flex cable looks fine, as do the sockets on both ends.
any Ideas?
thanks
John

[JohnG139]

BTW
the system boots normally and I get all the normal output to my desktop CRT when attached via the video port.

John

[scorps]

i think you will find its the ribbon cable i have replaced more of these than i care to remember you can buy a ribbon cable for your dell of the net there about 30 pounds dunno what that is in dollars. screens for dells as long as there the same size are nearly all the same even dell dosnt use the same ones all the time most are samsung in the uk
specs but as long as you find roughly the same year of model and series you will find they fit you can download the diagram from the dell wwebsite how to take your laptop apart its quite easy if you are carefull and do it a step at a time there are some slightly hidden screws tho