Here's how I took apart the LCD assembly for my laptop, an HP pavilion zv5000.
Why?As the back light bulb ages, it requires more current to stay on and start. Eventually, this current requirement will exceed the inverter's (a high voltage power supply) capability. This can lead to inverter damage (read: expensive).
SymptomsFor about a month or so, my back light starts off as red on startup and slowly returns to normal (white). This can take as much as 30 seconds to a minute. Much recently, my backlight has been turning off randomly, but the frequency has been slowly increasing. As of yesterday - I noticed a high pitched hum sound just before the light kicked off. My light would come on instantly if I hit the screen position switch. And lastly, if I turned the brightness down, most of the symptoms disappears - except the back light had a red tinge to it.
Solution1. Replace Bulb -- this is a $12 part
If problem persists:
2. Replace inverter -- a $70 part, however the bulb should always be replaced when the inverter is replaced.
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Step 1: Cautions
WarningThe following procedure will, without a doubt, violate any warranty you have. But who has to know? Take it apart and reassemble properly, and you won't notice :D
Your back light uses high voltage and sensitive electronics. So please, take care as not to damage these rather expensive components. Static build up will damage these components.
LCD's are surprisingly flexible given their material. But, they are fragile and should be treated with great care. Never pull on any cords and always allow the screen to rest on a firm, non abrasive, surface.
Reassembly WarningPlease understand, if you are not comfortable working with these components, do not take them apart. You may risk not being able to reassemble properly resulting in a back light that lights, but does not illuminate the screen, or partially illuminates your screen.
That's All, You Have been Warned
Step 2: Locate Screws
The zv5000's front bezel is held on with 4 screws and 24, count them, 24 snaps - 4 of which are large interlocking snaps.
Start by removing the screw covers located at the top and bottom of the screen. these are stuck on (sticker style) and easily pry up with a jeweler's flat head screw driver. Set these covers aside, and unscrew all four screws using a jeweler's phillip's head. Label and set screws aside.
By the way, you did remember to shut down your computer, unplug it and pull the battery? Right right? It's okay, I can wait.
Step 3: Snaps Aplenty... and the Cursed Glue!
Okay, so I lied... On top of your 24 snaps and 4 screws.... The LCD panel itself is glued to the front bezel. Ouch. Anyway, lets press on.
Open up your screen as far as it will go. I did this step with the laptop sitting in my lap. Look at the screen hinge - the portion that moves. There should be two, 8 centimeter sections on the left and right. Inside those movable section, there are two snaps each. these snaps are located about 2cm from the left and right sides of that movable section.
Now, using a jeweler's flat screwdriver as a pry bar, gently and carefully pry up on the snaps.
Once you've released these four snaps, begin to pull up on the bezel using pressure from your finger. You can also use the screw driver for a little extra leverage. As soon as you can, take a peek inside the screen and look for signs of glue tape. It appears that a metal strip covered in glue attaches the screen and bezel together. So move slowly. It is helpful to use a screwdriver to depress on the metal glue band to keep a concentrated pressure point from forming on the screen.
Work all the way around the screen. When you get to the latch, open the latch and continue prying. Then, remove the bezel completely.
Step 4: Remove LCD Part 1
In order to get to the bulb, we need to remove the LCD and gain access to the side and back panels - unfortunate. For this, I moved to a table and I used some inch thick foam, for support.
Begin with the mounting bracket screws (4). These were chromed in my case.
Next, unscrew the hinge side support/mount (see photos) screws (2). This separates the screen from the rear bezel for the next step.
Now, remove the screws (8 - 4 per side) from the side mounting support bracket (see image). To get your screwdriver in there, press down on the rear bezel until the screw is exposed. This is why we removed the hinge support screws.
After removing all 8 screws, firmly grasp the back light connectors and remove them (1 at a time).
Step 5: Remove LCD Part 2
WarningDo not reach under the LCD. Only Support the LCD by it's mounting bracket or by the metal edge supports.
Remove the LCD. This is done by lifting (straight up) on the top mounting brackets (2). The screen should then be free for removal.
Once you have access to the back of the screen - remove the tape holding down the lower portion of the screen cable. This will give you the freedom to flip the screen upside down to gain access to your back light.
Step 6: Removing the Edging (Partially)
I'm not quite sure what the official name is, so I'm calling it edging. It is the metal band that surrounds the perimeter of the screen.
The back light bulb is located at the bottom of the screen. To remove it, we need to gain access to the bottom portion of the screen - this involves partially removing the edging - removing a supoort bracket and then removing the back light reflector assembly.
First, remove the bottom support bracket. It should be held on with two chrome screws (beware - tiny).
Next remove the support bracket screws (2) - these are chrome. Label and set aside.
Now, remove edging screws (4). These are brass in color. I'm fairly sure you don't need to remove all of them, but you must remove the ones near the bottom portion of the screen.
The edging is held on with snaps around the perimeter and a bit of tape. Remove any tape in the way. You need to carefully insert your screwdriver into these snaps and pry them free. Pry all of the snaps on the bottom and the top two snaps on either side.
Now the edging should pull away from the screen (only slightly). With the edging pulled back, grasp the metal support on the bottom of the screen (this part has holes along the length of it). Rotate it around the screen (to unlock) and then pull away. This exposes the back light reflector.
Step 7: Remove Backlight
The back light is located inside the back light reflector. To remove, first pull the high voltage wire out of its holder.
Now, pull the reflector assembly straight out while lifting the plastic carrier away. Be gentle as the back light is in fact a tiny fluorescent tube - and contains mercury vapor.
The reflector assembly is attached to the transflective glass sheet. So, to remove you need to pull it off of this glass sheet which is what will cause most of the resistance.
Once removed, measure your bulb and order a replacement. Make sure your bulb will fit before ordering. I ordered my bulb from lcdparts.net
Step 8: Coming Soon!
Receiving your new bulb - installing and putting everything back together!
This so begs to be case modded :D