Computer Hardware Help → Dell Inspiron 8100 Laptop LCD problem

Oops... Removed this posting in regards to Jan's last post above... I misread WHO Jan was replying to, and I started to give the wrong info... Jan is correct. My bad.

-Tursiops_G.

I have a Dell Inspirion 3700 for a customer. It seems while I was replacing the fan that sends air out I may have damaged the screen. I was very gentle with the parts though! Now the screen is all dim and I suppose it's the CCFL. The CRT connection works. This laptop is pretty old so I don't know if I can even find the correct parts for the LCD. I haven't had much luck yet.

Ok, if you read the post above you know my situation.

I got another laptop of the same kind. My partner happened to have one that was fried. Well I took the screen from that one and swapped and it was the same. So it's not a bad screen. I don't understand what else it could be? The laptop works in VGA output. It has to be something on the mainboard.

The second laptop that was fried, I found the peice that was bad. I don't know what it is... I think it's the Powerboard from what I've googled. Is this the Inverter? Or is the Inverter inside the LCD. If it is, it cannot be the Inverter.

Where is the video card? I'm not a huge laptop junkie, but if I replace the power board from the Dim LCD laptop into the fried one, the fried one works. So that eliminates this part from being bad.

What else can it be? It cannot be the screen, the powerboard or the video card. Or can it still be the video card even though it works in VGA mode? Can it be the motherboard itself?

UPDATE

Well I switched what I assume to be the CPU (videocard?) and it still did the same thing. I would assume now that it is the motherboard. I think the video is integrated. But it still doens't make sense that it works in VGA mode.

I'm going to order one on Ebay and I'll let you all know if it works.

freakout/drossvirex

have you got the LCD screen to work yet?

i am in the same EXACT boat as you. i have the exact same 15.3" hitachi sxga+ TFT lcd screen with that same model number: TX38D99VC1CAA.

but i believe i know what we did wrong. while you had ordered a very very similar lcd inverter, made for a samsung lcd , i had ordered one made for an lbm lcd.

but now i just realized this inverter model is a j12i005.00 ambit chip. and looking to track one down currently. there is nothing on ebay, and google results a few unstocked items around. i will follow this thread up as soon as i get something going.

ps. my screen blinks red on bios boot then the backlight is off until next powerup.

Moderator Action
The post that was here, and all followups to it, were moved to a new topic .. » LCD problem- Dell Inspiron 8100

Holy thread resurection, Batman!

I too am in this same boat now.

Grrr..

Insperion 8100, with the exact same hitachi display as pictured above (TX38D99VC1CAA) and same story as Daveywave,
Screen blinks red for a split second on power up, but then remains off untill reboot. I used to build OIT embedded computers with either 10.4" or 15" displays, and in my experience Even tho I had replaced maybe 60 Inverters, there was only 1 CCFL failure that I recall. Those screens were NEC tho, not Hitachi.

So, has anyone had any luck finding a replacement card? I called screentekinc.com as they have the whole display module (for ~$500, IIRC) but dont sell just the inverters.. Screentek referred me to www.mpdparts.com who said they didnt carry dell 8100 stuff..

So, Here I am again, Stuck.
Grrr..

-Jason

Quick update;

After a lot of web searching, I found a company (Bliss Computers) that seems to stock the OEM replacement inverter. Its $65 +$10 shipping. I ordered one, and will let you know how it works out.

-Jason

I had the sme thing happen with an Inspiron 5000 just after the warranty was up. I would advise you to BACK UP YOUR DISK now. Immediately after my LCD went bad, it worked on a CRT, but soon thereafter, it did not work on CRT either. And the whole machine started to go bad...just a day later.

At that point I could do nothing with the machine except take out the HD and get someone to extract my files for me.

Fortunately, I had purchased the machine on American Express and that covered 1 extra year of service...so after a repair shop declared it dead, Amex paid for my Inspiron 600m to replace it. Not so bad...but it was a problem while my machine was down.

Back up that disk.

Bliss board came in.. Visually, its a perfect copy of the removed card.. Will post installation results tonight.

also found a company selling the CCFL tube for this display for $9.99

Will have more info later.

-Jason

Did this repair your issue?

Nope. Put the new inverter board in, plugged it in, and tried to fire up the laptop.. Same issue. Flashes red for a slit second upon boot, then not agian..

So, due to the process of elimination, there are only 2 possible problems left. 1) The CCFL tube itself is bad, and 2) the mylar cable that poweres the inverter is bad.

I decided to try for the CCFL first, With a deep breath, I started prying the retainer tabs on the screen open, to get to the tube..

The tube itself is running along the bottom of the screen, starting in the corner where the wires dissapear (Pink & Gray). I opened the screen only enough to unsnap the silver channel that holds the glass distibution plate, and the various "coating" sheets in place. the tube is running inside a channel in the white plastic frame of the screen. Its not really difficult to get out, however, i was astounded at how thin the CCFL tube really is.. Is a 2mm dia. tube, really no bigger than the pink wire going to it. Care and gentile handling are the name of the game here.

Once out (and as the screen sits now) Upon closer inspection, I find that the tube ends are blackened rather badly, and that a small bit of plastic had melted to one end of the tube, So at this point I have a rather good notion that the tube itself, and not the inverter was bad in my case. I will be ordering the tube sometime this week, and hope to get it in, and installed. Once everything is here, I will post website addresses, and part numbers, along with full prices here, as Im assuming some of the previous posters dont have their problems fixed yet..

-Jason

Wow, That's unusual.

CCFL tubes normally have a 20,000 to 25,000 Hour Service life (that's down to 50% light output, BTW.)

If you don't have anywhere near that amount of hours on it, then You may just have had a Defective CCFL tube, or a defective Tube connector...

-Tursiops_G.

From what I've read over the years about notebooks, it's generally the CCFL that goes first rather than the inverter. I suspect it's a combination of issues: users often set their displays to maximum brightness, frequent opening/closing of the lid and cycling of the lamp, and inexpensive inverter and backlamp controller designs. The small diameter of the tube doesn't help either since the lid of the notebook isn't that well protected from pressure (from placing heavy objects on it).

Get some!

I am posting from the offending laptop, with display glowing in full glory!

Okay.. Yup, it was the tube

They are rather difficult to replace, and the replacement tube quoted above was ~3mm shorter than the original...

I will post pics of the process, as well as a tutorial of what I did come tomorrow, when Im not on dialup.

But its done, in, working, and a $20 fix.

Note: This panel is *not* considered a "replaceable tube panel. There is some soldering, and rather delicate yet frusteratingly complex steps involved.

Now: To log off, and put all the screws back in...

-Jason

What size was your LCD. I replaced mine because the screen was scratched, rather badly by my little girl. I have the original one sitting now in a box.

Okay.. Once you have the bulb out, pull off the rectangular white rubber end caps, and set them aside.

Heres the old (with the wires attached) and new (on the cardboard) tubes.

Info:

I got the tube from »www.lcdpart.com

The part number is ms20305 (Im assuming 20305= 2.0mm dia, 305mm long)
Direct link: »www.lcdpart.com/Products ··· 305.html

Cost was 9.99 for the tube, 9.99 for S&H, plus California tax.

Total cost: $20.85

The inverter I purchased (as it turns out, I didnt need)
I got from Bliss Computers. »www.247laptoplcd.com
Part number: J12I005.00
Price: $65.00
Shipping $10
Total: $75.00

Direct link to part:
»www.247laptoplcd.com/lap ··· pair.htm (first part on the left)

Bliss takes orders through paypal.

You can also order the whole screen from bliss, for ~300 refurb, IIRC.

Welp.. Hope this helps someone out there.
a $20.85 fix for what dell said was going to cost more than $1000 to repair. LOL

Good luck, and have fun..

-Jason

Jason, was it short because you mis measured or why?

Also, do you know what the Voltage output should be for the inverter to the tube?

Thanks

the tube was short, as that was the only replacement I could find. A few mm shorter hasnt caused any noticable darkening on either side of the display.

Im guessing that these companies that make / sell CCFL tubes probably only do so in certain "standard" lengths. It *may* be possible to find an exact length replacement *somewhere* on the web, but for my (impatience) I decided to go with a reasonbly easy to find replacement.

The Website I ordered the tube from touts it as a suitable replacement for the Hitachi Display I had, and such has turned out to be true.

As far as Voltages, I can only guess given the length of the tube, and dia. Id *guess* the breakdown voltage ("Kickstart") to be in the neighborhood of 1,200-1,500V, with the hold-on voltage somewhere in the 600-700V. But, again, these are just guesses.

I do know quite a few of the 300mm long color CCFL used in custom computer lighting run at 650-690V.

Hope this helps!

-Jason

Thanks Jason, I am just looking for backlight to fix my compaq laptop lcd. For $20, I am sure will give it a try.

P.S. This is the instruction on how to replace CCFL, This is from the web site you order the tube.
»www.lcdpart.com/images/c ··· tion.pdf

yup.. Thats a rough guideline on how to replace lamps on a "Replacable Lamp" screen.

Alas, These arent a replaceable type screen. *Sigh* It would have been *sooo* much easier if it were.. LOL

-Jason

I have an Inspiron 8000 screen that I am willing to give away to anyone who wants it. I just purchased a new flex cable and backlight for it. Someone can use it for parts, particularly the CCFL backlight and flex cable.

I have a question: I was given a NEC 1525m LCD. It goes completely dim right after turning it on. If I hit the on/off button to shut it off and then again to turn on I can see the display for less than a second before it goes completely dim again. I searched the web and mostly found everything leading to replacing the "cold cathodes." So I removed the cold cathodes(first time ever opening a monitor; removed every screw I saw). There were two cathodes (one on top of the screen and one on the bottom). Is there any visible mark on the cathodes to tell that they are bad?

Any input will help. Thanks.

No reliable marks to tell that theyre bad as far as I know.. A darkening of the white tube at either end shows that its been used, but not nessicarily bad.

Sputter is usually the main cause of CCFLs going kaput. When the lamp turns on, a small amount of either the cathode, or anode (I dont recall which) literally vaporizes, and If memory serves me, somehow reacts with the mercury vapor causing it to become less effective over time. Eventually it gets to a point that the inverter cant keep up with the voltage demands of the tube, and shuts it off.

Even tho these things have anywhere from a 15-50 thousand hour "Half life" Its cycling the bulb on and off that puts the most wear and tear on it. Ive heard estimates from 10,000 to 50,000 cycles can kill the bulb.

Since you have the bulbs out, the cheapest solution would be to buy replacement bulbs and give them a try.. If that doesnt fix it, then its time to locate another inverter.

Hope this helps!

-Jason

Jason
Only one(the top connector)of the CCFL "sputter"'s. The other (bottom) CCFL does nothing. So I interchanged them(thinking that the bottom CCFL is the bad one) but again only the top one sputtered. Is it normal that only one side gets power when the CCFL's failing?

Thanks.

Hmmm.. Unfortunately thats not to telling either..

It is starting to sound like the inverter card, but.. A bad lamp can cause this kind of problem too.. If the inverter cant start 1 of them, then it usually doesnt get the other one going either.. Depends on how smart the inverter is..

Sorry I cant give you any more help.

Id still say replace the tubes first.. Theyre probably the cheapest, easiest to find part (compared to the inverter)

-Jason

I am in the midst of the I8000 backlight dimming problems
as well. I would love to take you up on your offer of a free I8000 screen. Please write: witslo@yahoo.co.kr Thanks.

luvwarmthpeoplepccom wrote:

I have an Inspiron 8000 screen that I am willing to give away to anyone who wants it. I just purchased a new flex cable and backlight for it. Someone can use it for parts, particularly the CCFL backlight and flex cable.