Comments on: How to replace backlight lamp (CCFL)

By: Supertechster

Supertechster — Sun, 27 Sep 2015 19:52:35 +0000

Looking at the reflestor, one can see the obvious channels intended for the bulb with tiny ‘o’ rings to shockproof and center it and the rest of the part which includes a 2nd slot for the LCD/Screen, Diffuser and other clear sheets or polarizing filters necessary for proper operation and even distribution of light. The Slot which contains the tube, Also MUST contain the thin totally-white backing sheet and the 2-3mm plexiglass sheet which edge must be fingerprint free and sits against the lamp, catching and transferring all the light from it throughout the display without actually sending it ‘out’ into the room ie: all the light produced by the tube is captured inside of the clear plexiglas sheet, which is directly in front of the polarizing filters, skin sheet and LCD display. Got that? The thin white plastic sheet AND the thin clear plexiglass sheet must both be in the same slot/channel/groove the tube is in..t – nothing else. The rest of the filter and slip/skin sheets and the LCD display go in the other slot/channel/groove. Any other way and you will get partially lit or halo-looking displays after tube replacement. To do this easily, I lay the entire display on the table, assemble front to back (LCD, filter, protective sheet, filter, protective sheet, then put toothpicks on the edges of the screen to hold everything up at an angle without fingers, and then carefully slide/push/wiggle/ease all of that into one end of the slot that does NOT have the tube. Then follwith the Tubre in it

By: Scott

Scott — Sun, 30 Aug 2015 17:34:33 +0000

Is there some particular reason you did a complete panel disassemble for this replacement? Why not just loosen the bottom and sides? Much less risk of major screen errors/damage/light leakage, and less scary for those who attempt this repair.

By: Mary

Mary — Tue, 28 Jul 2015 11:53:35 +0000

Hello,
i was wondering, how many back lights are they in a LCD screen ?
Thank you very much

By: edavis

edavis — Fri, 29 May 2015 02:24:51 +0000

I removed the connector to the back-light while the battery was plugged in. I noticed a sound like gas coming from the back-light. I quickly reconnected it and then removed the battery. After reassembling everything, the display lit up but it was just a white screen. Did I damage the back-light by disconnecting it with the battery left in? This is a Sony laptop.

By: FoiDeÃ©

FoiDeÃ© — Mon, 13 Apr 2015 05:43:56 +0000

I’m facing the same screen prblm.my scrn got broken and i bot new one and after fixing it just as i turnd it on it displayed and went off and i replc anthre one and it went off again.
Help me guys

By: Paul B.

Paul B. — Thu, 05 Feb 2015 04:01:47 +0000

Great tutorial, sir. Thank you. I have replaced a few backlights now. It gets easier each time. The last one was an HP G60, and the problem was a burned-out solder connection at one end of the BL. I resoldered it and was on my way.

The problem I’m having is that the lower edge of the screen has a bright glare that extends up maybe 1/4th inch. I’m sure it’s due to not replacing the “deflector”, if that’s what it’s called, correctly. It’s a flexible flap that prevents the intense light from coming out to the surface of the screen. Evidently it needs to be sandwiched in just so. I placed it under the outer screen layer, but the result, while good, is not perfect.
BTW, I did the job without disassembling all the screen’s layers.

By: cj2600

cj2600 — Mon, 22 Sep 2014 15:37:08 +0000

In reply to chi. @ chi,

Hi, can you explain why the bottom of the screen is brighter than the top half after a fresh bulb replacement? This was for a ThinkPad t43 with a LG panel. I did a similar replacement for another t43 but with an idtech panel a while back and it went without a hitch.

Probably the new CCFL bulb is not aligned correctly or maybe the reflector not aligned correctly.

By: chi

chi — Thu, 04 Sep 2014 11:19:50 +0000

Hi, can you explain why the bottom of the screen is brighter than the top half after a fresh bulb replacement? This was for a ThinkPad t43 with a LG panel. I did a similar replacement for another t43 but with an idtech panel a while back and it went without a hitch. Thx

By: cj2600

cj2600 — Fri, 30 May 2014 18:54:26 +0000

In reply to Marie. @ Marie, The new backlight bulb should work outside the case. It doesn't matter if the bulb is mounted to the case or not. You tested everything correctly. I think it's either your new backlight lamp is defective OR it's not compatible with the inverter somehow (which I doubt). I've been using the same backlight lamp for years and tested multiple computers and never had any compatibility issues between CCFL and inverter. Probably your new backlight lamp is defective. Why don't you replace the entire screen? They are cheap these days. Replacing the backlight lamp is very difficult even though it might look easy on my pictures.

By: Marie

Marie — Wed, 28 May 2014 21:55:51 +0000

Thanks for putting this page together. I was wondering if you could help me determine a defective bulb… Here is my situation:

I have 2 identical laptops — 1 with a working screen, the other not. On my working computer I can turn it on, and of course the backlight and everything comes on. It is completely normal. I bought a new set of ccfl bulbs with a harness for my non-working laptop screen. Before I experiment with my old laptop, I wanted to verify that the bulbs are working. I opened my working laptop and ONLY disconnected the ccfl plugs that go into the inverter. The rest of everything is in place–motherboard connections, lcd connections, etc. The only difference is the new bulbs and their connectors.

Well, if I connect the new bulbs to my working computer’s inverter, they flash on for half a second and then go off, never turning back on even when it should be at full brightness. I can follow the boot process with a flashlight behind the screen which shows when the bulbs should be fully bright. I am thinking it may be a problem with the wiring/soldering on the harness…? If I reconnect the plugs from my working bulbs, they come on accordingly. If everything is connected IDENTICALLY, does it make and sense that the new bulbs would not turn on outside of the encasing?? I got inspired by seeing your picture of the bulb on outside of the fixture…

Thanks in advance for any help… I really appreciate your time.

Marie