I just traded around and got a KDS lcd for free. My first lcd. I hooked it up and everything is fine for a few seconds then the screen goes blank. The power lite is still lit but no display. I can turn lcd off then on and everything is fine for a while.
Is my monitor shot?

Looks like the monitor has a heat problem that courses false contacts or so...

No warranty on it? Then I would open it and reseat the cables inside the screen: just pull them out of the contacts and put them back in. Be careful if you use contact-spray that you don’t spray on your display, which could heavily damage the screen…

Thanks I will try this.
The monitor was stored in a cold storage shed the previous owner told me. Could this effect it some how?

It depends on the temperature, but you say that the screen looks fine for some time so I guess it didn’t affect it. If the screen was not packed the contacts could be oxidized when it was not stored in a dry place. I think you have to open it and look at it first .

this could also be a backlight issue, if the image is still shown but extremely faintly.
what angle are you using the screen at ?

I removed 4 small screws all on the same side of monitor (top), I tried to gently pry it apart but no-go, how would it come apart?

Some parts could be "clicked" together, so that means it was made to be assembled, but hard to take a part.
Can you give the model number so I can see what model it is?

It is a KDS K917s
Thanks

Hard to see with the info on the internet, but I’m sure it’s clicked together. Use your fingernails to open it a bit, not with a metal screwdriver that would damage the screen. If you’re lucky it pops open a bit or you can see where the click-connections are hidden.

I got the plastic ring off, and took the 4 screws that hold on the screen. Many sets of wires plus a metal cover with more wires. Which ones do I need to look at?

Okay, let’s continue the operation .

Now, unclip each connector and clip it again, starting with the one that comes from the screen... Check inside the connector if you can see some white or green oxidation...

Peteski told you it could be a backlight problem, so I need to know how the screen looks like. It goes blank you say? Totally white? Or Black?

It goes black but power liter stays on.

But you see something on the screen? Is there any backlight?

Nothing on the screen. I asked the guy who had it before me, he said when left plugged into wall for a few days it worked for him. I left it plugged in overnite and now it works. What do you think is wrong with it? If I were to guess myself I would guess a cap going or gone bad in power supply. Am I close? Is this monitor going to quite me soon?

It could be a capacitor indeed. Did you look at them? In addition, does it have an external power supply?

The power supply is intergrated so not easily fixed. How long do you think the monitor will last?

Well, you are wrong there, when it’s integrated it’s easier to fix then an external power supply (well you could by a new external one, but those are expensive). Did you open de metal box?

I havnt opened the metal box yet. When I do what do I look for?

@dirtwarrior- Would it be possible for you to post a link to a picture of the inside of your monitor? puntoMX might find it useful and I am very curious as to what it looks like in there.


DL

i'm getting the same problems as you dirt warrior... did you ever resolve this issue?

how about checking the monitor power down settings in the computer......

When the main screen comes on it last maybe a second.

but did you actually check the powerdown settings? Not the screen saver, but on control panel|power

And have you tried another video card before you start tearing down a costly LCD panel with no real knowledge of what you are doing.

my best bet is there is something wrong with the caps on the monitor board... that seems to be about the only thing i came up with on google.... there isn't much but what there is isn't in english

Cool that we bring up this topic again.

As I’m fixing more and more screens these days I found out that it’s a general backlight problem with many models/brands.

Most of the time it’s a problem with bad transistors that drive the backlight coils, bad soldering points and the coils them selves.

To replace coils will be hard as they are not sold at your local electronics-store, however, the transistors are basic pull-transistors that can be found in almost every electronics-store and re-soldering the bad/cold points is a peace of cake.

so how do we go about figuring out which are bad points and all that jazz? is there a decently easy way to do this?

also, i got mine for free from an aunt and uncle, they said it didn't work, i had it running for about two days and then i turned it off, when i went to turn it back on is when it didn't work... i'm letting it sit for a while, but i'd like to fix it 100%

There are no capacitors that drive the backlight, however, the power to the backlight module has capacitors but if those were damaged then most likely the screen would not even light up.

Exactly, you have bad transistors; they overhead fast and thus aging goes faster too. Replacing them isn’t hard if you know soldering a bit, but before you remove them I would check your local electronics-store if they have them, or at least can order them. They should be cheap and you don’t need more then 6 of them (never saw a screen that used more then 6 and 2 coils). What brand/model do you have? HP?...

kds k917s, 900d.

how do i know which are the good and which are the bad ones... i'm a n00b when it comes tho this kinda stuff.

Replace them all, they are cheap; let me see if I can find the module lay-out.

like those are what i'm replacing right? and i can't find any blueprints or whatever for the boards... also i'm just replacing the powersupply board right? not the one with the chip in it or whatever? would pics help?

Those are not transistors, those are capacitors and those aren’t your problem.

Take the board out and make 2 pictures; one from the back and one from the top, if possible on high resolution and using www.kwikpiks.com to upload them. Remember to use the thumbnails to post here and the link to the bigger version .

I have a similar problem and can send a few pics of the boards in the monitor if it would help.

Please do. Just follow PuntoMX's directions.

Mark

if the monitor just stays on for a few seconds and turns off, i suggest double checking the power adapter for it. I have two HP f1703 monitors, and if the amperage is not high enough (3.5a minumum) the screen will turn on for a few seconds and then shut off. you may be interested in checking that for a much simpler fix.

I'm facing the same issue here, it seems to be a common problem. I'll crack this bad boy open soon and post some hi-res pics.

Edit: For about a month before the monitor s*** the bed, it was making a high pitched squeal. I have no idea if that helps diagnose the problem at all.

That sounds like the coils (resonance), those are not hard to replace but hard to get, also it’s most likely that you need to change the transistors connected to them too.

Digi-Key wouldn't have them?

I can´t tell, but you could give it a try...

You have to take the module to the shop to show them what you want, the coil looks like this more or less:

It looks like the problem is a group of 6 capacitors on the power supply. 5 of the 6 are bulging. They're all the same, 470µF, 25V. Radio Shack carries 470µF 35V caps, I'll be picking up 6 tomorrow and we'll see how that goes.

The bezel was a b***h to get off, I snapped pretty much all of the clips on the sides.

So you´re lucky that the capacitors are the problem would never think they would make that sound as they normally just pop and that it. They o make a sound before the pop but I only heard that when putting on to high voltages (done for testing by me).

If the plastic clips are broken, you can use silicon glue to get it back together. It´s easy applied and can be wiped of where it´s not needed. It takes some time to dry, that´s for sure.