Laptop display - all red but readable

Sounds like a ribbon cable problem to me. I'm assuming that it displays properly on an external monitor. If you don't have the chops to open it up and reseat the connectors (or replace the cable), it should at least be a cheap fix.

Try moving the display open and closed (almost) while viewing. If the image changes--at all--while doing so, the diagnosis is all but confirmed.

jak

It's been reported that a bad backlight can cause a reddish tint. Most of the reports I've seen have been related to thinkpads. If by "red" you mean that examination with a magnifying glass shows that green and blue are compeltely dark, that's probably a different matter. mike

up

image

I have tried that, plus pushing, pulling, twisting, etc. It doesn't vary at all.

Bob

I checked with a stylus microscope. It looks as though one color is not working at all. I see varying brightnesses of 2 "bars" on each pixel. The red works fine, the one to its left works also. I can't tell for sure what color that is. The Bar to the right of the red is always blank.

What signals typically go through the ribbon cable? Can anyone suggest a reference for this sort of info?

Bob

Time to get out the screwdriver...or the phonebook.

jak

That'll be the screwdriver. I'm just trying to get a head start, since I've never dealt with this sort of problem before.

Bob

Ribbon cable is a fairly common failure with laptops. And often the only thing wrong, yet most makers perversely refuse to supply the part for an easy repair.

One other possibility comes to mind - some laptops have dipswitches to set for display type/resolution. A Presario that I had to swap displays on gave me a red screen until I figured out the right combination.

If some> I just acquired a laptop (Dell Inspiron 3200) which has a problem on the

Very good. I talked to the guy I got it from yesterday, and he said that he took it somewhere for a virus problem and it came back with this problem. I will research this possibility. I don't know why they would go inside for a virus, but who knows?

Bob

Hmmm...

It's possible that this could actually be a software problem. Have you checked to make sure it's using the correct video driver? Rather than let Windows auto-detect the display, I'd download the driver from Dell and install it manually.

If there was a virus, there's also a possiblity that a supporting .dll or other file could be corrupted or the wrong version. This could be a real bear to troubleshoot.

Eric Law

I did try booting off of a windows 2000 install disk, and the problem was still there. I will try downloading drivers from Dell and see if that helps. Wait. The problem also exists on the boot up screen. I guess I should look in the setup for screen related settings.

Bob

checked to make sure it's using the correct video

driver from Dell and install it manually.

other file could be corrupted or the wrong version.

he

problem. I

for a

Nah, I should have thought to ask that. If it's wrong on the boot screen, it's not a software problem (unless there's something REALLY weird going on in the BIOS).

I don't think you're going to find a setting in there that says "make the screen all red" ;^)

Eric

I disassembled the machine enough to get to the LCD cables and unplugged/replugged both ends - no change.

Looking at the screen with magnification, It seems like the red "bars" are bright, the ones to the left of them are dim (enough that I'm not sure of the color), and the ones to the right of the red are off. This is on things that I assume should be white. My next question is: Are there any signals going through the cables affecting this sort of problem, (meaning it could be a problem within the processor/mainboard part of the unit) or is this really a problem solely in the LCD unit?

Bob

it's not a software problem (unless there's

screen all red" ;^)

helps.

look

Now that you have it apart, check the individual traces on the cable with a multimeter. It's very possible that one or more of them is open. It would be nice if it the cable was just loose, but they often break as well.

You never did mention whether the unit works with an external monitor.....

jak

I once saw a thinkpad that had a red back light. It was so red I thought the display or cable had a problem at first.

Look at a completely black screen. If black is dark, but has a red tint, then it's probably the back light.

The other thing you can do is take apart the screen so you can see the back. It should glow a bluish white. If it's pink, you've found the problem. Andy Cuffe

snipped-for-privacy@psu.edu

would

I will do the cable check. I haven't tried with an external monitor, but was told when I bought it that that worked fine.

Bob

Lots of them have an internal jumper that clears CMOS if the password has been lost or you need to start from square one.