Member Avatar for 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:

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Brief, practical summary and step-by-step for later readers:

When the laptop shows video on an external CRT but the internal panel only lights, or shows vertical stripes or odd spots, the problem is almost always inside the display assembly or the signal/power path into it. The fastest way to narrow it down is a short, ordered set of low‑risk checks that separate "panel" from "inverter/cable" from "motherboard" faults.

Recommended checks (in this order)

  1. Flashlight check: with the machine powered and the backlight on, shine a bright flashlight at a low angle across the screen. If you can see a faint desktop/boot image, the panel is receiving video but the backlight or inverter is at fault. If you see nothing, the panel or the video feed to it is suspect.
  2. Safe reseat: remove battery and AC, remove the display bezel, and carefully unplug and replug the screen cable at both ends. Inspect for torn wires, bent pins, corrosion or obvious damage.
  3. Wiggle test: with the lid open and the machine on, very gently wiggle the cable near each connector—note any flicker or colour changes. That points to a failing cable or connector contact.
  4. Inverter inspection: look for bulging electrolytics or scorch marks on the inverter board; those are cheap, common failures and can produce dim or uneven lighting.

If a replacement panel shows a vertical red stripe or bright circular spots, the replacement panel is likely defective or mismatched. Panels can share a mechanical size but use different driver ICs or connector pinouts; confirm exact part number and pin count before buying another. Cleaning the panel-to-driver mating pads with high‑purity isopropyl and re-seating can sometimes restore a marginal contact, but internal alignment is delicate and a professional press/jig is often required.

Practical decision path: flashlight test → reseat cable → replace inverter → try a verified exact‑match panel → if still bad, suspect motherboard/display output. This follows the observations and advice from , and ; use Dell parts lists or the service manual to verify exact panel part numbers before buying replacements.

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Member Avatar for 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.

Member Avatar for 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?....

Member Avatar for TallCool1

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

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 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.

Member Avatar for S911houston

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

Member Avatar for 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.

Member Avatar for 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?...

Member Avatar for whipaway

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

Member Avatar for S911houston

Thanks for the replay ! will do!

Member Avatar for S911houston

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?

Member Avatar for JohnG139

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

QUESTION FOR TALLCOOL1

In the latitude, the LCD

Member Avatar for JohnG139

sorry - hit the <return>

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

Member Avatar for 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.

Member Avatar for 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

Member Avatar for JohnG139

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

John

Member Avatar for 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

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