Re: Laptop LCD screen issue...

The backlight is out. Basically, there is a 98% chance that it's either the actual backlight lamp (actually a fluorescent light tube) or the inverter that produced high voltage (600 to 1,500 volts) to power the tube. It is very difficult to tell if it's the tube or the inverter, but the inverter is much more likely unless the tube (which is glass) has been physically broken.

Inverters should cost $25 to $95, but they are very hard to get. You need an exact replacement, and it's most likely an HP custom part. It's located in the lid, which will have to be taken apart for ANY repair.

The lamp is physically inside the LCD panel, but is a logically separate component. It is [almost always] separately replaceable, but more than 90% of the shops you would take it to would repair the problem by replacing the entire LCD panel. A bare generic lamp is about $15, but does not have the wiring harness or connectors to install in the laptop. A lamp assembly from HP, IF THEY OFFER ONE AT ALL, is probabaly $90 to $140. A new LCD panel (with a lamp) is likely to be $300 to $900 (likely more than the laptop is worth).

From your description, the hard drive is ok and any files on it could be gotten off it relatively easily.

Most LCD lamps in laptops have the exact same connector. If it was my laptop (I service laptops), I'd try to light the screen by plugging the lamp into an inverter in another laptop (all I care about is the connector, and if the lamp lights up at all). If the lamp lights, it's definitely the inverter. EXTREME CAUTION: As noted above, the inverter output is high voltage. Potentially LETHAL high voltage.

If I absolutely could not pin down lamp vs. inverter, the inverter is more likely the cause than the lamp, and is easier to replace. I'd look on E-Bay for an inverter, or for a dead laptop or a laptop with a clearly physically busted (cracked) screen of the same model, as a "donor" part. You can also try an HP parts source if you can find one.

Frankly, unless you have some training and experience in changing an LCD panel lamp, your chances of doing it successfully the first few times are essentially zero, so you almost do need a whole LCD panel. Again, I'd go to E-Bay, this time looking for a dead laptop with (presumably) a good LCD panel. You can often find LCD panels on E-Bay in the $50 to $150 range.

If you know what you are doing and want to try a generic replacement of the lamp (I strongly advise against this unless you are very experienced and a very good technician), salvage the wires, harness and connector from the old lamp cutting them off right at the lamp. Digikey and Mouser carry generic replacement lamps. You will need the dimensions (length and diameter, in millimeters) of the old lamp.

Best of luck.


defyingtheworld1 wrote:
Forgive me, this is my first post and I don't know all of the correct
terms I should use and probably won't post all of the information you
guys need to help me, but I'll try my best.

My dad used to run his own computer business (mikeshardware.com) out
of Burlingame/San Francisco, CA.. and I went to him with all of my
questions and help. He was killed in a motorcycle accident in
November 2004; however, a week after I mailed him my laptop to be
fixed. I haven't been able to bring myself to ask anyone else to fix
it until now.

I took my HP Pavilion laptop
(http://www.mikeshardware.com/reports/report_hpn5440.html)
on a church trip to Panama City Beach, FL one summer. It was on a
charter bus, in its thick, protective case, in the overheard
compartment away from the students, and as far as I know, it wasn't
dropped or stepped on or anything. The first couple of days, it
worked perfectly. The sole purpose I brought it with me was to have
someplace to store all of the digital pictures I was taking with my
Olympus.. it was rarely used.

Around the second or third day, I turned the computer on and couldn't
see anything on the screen, unless it was outside in the daylight,
and tilted it a certain way. At night, it was impossible to see
anything on the screen. It just seemed to go out on me.

My aunt seems to think that it's some kind of blown fuse. I didn't
think it was a blown fuse, because if it blew, then I didn't think
I'd be able to see a thing.. and I could still make out the icons and
images on th screen. I was able to talk with my dad before the
accident and he told me that the humidity could have had something to
do with it (because it was ice cold in the bunks, and super hot
outside.. and taking it from inside to outside may have produced
condensation on the inside of the computer.) He gave me several
drying-out remedies to try, but I never opened or altered anything in
the computer. Needless to say, nothing worked. He thought we might
have to replace the screen, so I shipped it to him.

Well, since the accident, my dad's sister has had it, still in the box
and in her house.. she is mailing it back to me because she can't
bring herself to ask anyone else for help.

I was just wondering if you all had any ideas as to what it could be.
I also don't even know who to take it to.. because I hear that
computer repairs can be costly, or they can be relatively inexpensive
but you'll still get ripped off.

This computer is very special to me, because my dad was really only in
my life for a little over a year. My parents divorced when I was 4,
and we didn't have contact again with him until I found him on the
internet 15 years later, July 2003. This particular laptop was one of
his personal laptops, and when he discovered that I was in college
without a computer of my own, he sent it to me. It had several
pictures of him and his wife and life in California and saved IM
conversations between the two of us and other things on it that he
sent me.. as we never got the chance for a face-to-face reunion. He
was the only one who ever worked on it.. or did anything to it, and
I'd like to keep it in as good of working order as I can. I actually
plan to use it sparingly when I get it back and get it fixed. It's my
last link to him, and I don't know what I'll do if I can't fix it..

Thanks in advance for any help any of you may be able to offer.

ps- I don't have the laptop back in my possession just yet, but it is
apparently on its way soon..

.

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