right now my t43p’s screen goes out regularly, every 2-5minutes. sometimes i see something faint in the background, more likely if i have white-colored windows opened when it happens. but most of the time i see nothing at all back there. and my usually white letters aren’t reddish or pinkish at all. i can’t figure it out.

Most likely this is inverter failure or CCFL failure (backlight lamp inside the screen). Cannot tell without testing the laptop with another inverter or lamp. If you have to guess, try replacing the inverter board first. There is a good chance you’ll fix the problem.

lcd screenless in Seattle.

Notebook works ok with external monitor.
However, when i return both original SXGA screen with original cable, it still shuts down
immediatelly 3-5 seconds after I press power button. Same thing also happens with XGA screen from T42.

So, is motherboard damaged, how can I determine that?

Unfortunately, there is no way to tell what is wrong without testing the laptop with another KNOWN GOOD SCREEN.
It’s possible that when you installed a “wrong” XGA screen you damaged something on the motherboard OR maybe fried the video cable.

Notebook works ok with external monitor.
However, when i return both original SXGA screen with original cable, it still shuts down
immediatelly 3-5 seconds after I press power button. Same thing also happens with XGA screen from T42.

So, is motherboard damaged, how can I determine that?
Do you have any more clues after I provided to you with this info?

If i can be sure motherboard is not damaged I would by a new screen, however, if i cant determine if motherboard is damaged it would be too risky to buy a new screen.

I did replace ONLY old lcd panel with new one, all cables, screen box, and other things have not been remmoved, all are left from previous screen.

PROBLEM:
After I turn on notebook it works 3-5 seconds (it works until LCD screen should turn on), and then it shuts down
automatically. I can NOT turn on notebook again before I remove baterry and put it back again.

Take a look at the parts list again. SXGA and XGA screens require different video cables. It’s possible that using a wrong screen with the original cable damaged the motherboard.

Mystery is I also tried to return original SXGA screen with broken lamp to my notebook, but same thing happens again – it shuts down automatically after 3-5 seconds. Before I replaced original broken SXGA screen, I could still turn notebook on,
and no matter picture was pitch black on notebook, I could still get picture on my TV (connected via S-video cable to notebook).

Here’s what you can try.
1. Turn off the laptop.
2. Remove AC adapter and battery.
3. Disconnect video cable from the LCD screen. Do not connect any screen.
4. Disconnect CMOS battery.
Wait for a while and try turning it on with the external monitor. Can you get external video after that? If yes, connect all back together and install the original screen. Test again. If it works, try replacing the video cable and only after that installing the new XGA screen.
If the laptop still shuts down and will not stay on, it’s possible that you damaged the motherboard.

Since my LCD backlight lamp was dead (as diagnosed by IBM authorized technicans) and buying new screen was not an otpion as it costs too much (about $500), I replaced my old LCD screen with 14″ XGA 1024×768 (manufacturer – LG) from T42 notebook (screen FRU 92P6726). Both screens listed here: http://www-307.ibm.com/pc/support/site.wss/MIGR-58431.html

I did replace ONLY old lcd panel with new one, all cables, screen box, and other things have not been remmoved, all are left from previous screen.

PROBLEM:
After I turn on notebook it works 3-5 seconds (it works until LCD screen should turn on), and then it shuts down
automatically. I can NOT turn on notebook again before I remove baterry and put it back again.

Mystery is I also tried to return original SXGA screen with broken lamp to my notebook, but same thing happens again – it shuts down automatically after 3-5 seconds. Before I replaced original broken SXGA screen, I could still turn notebook on,
and no matter picture was pitch black on notebook, I could still get picture on my TV (connected via S-video cable to notebook).

What went wrong, any ideas? Is something fried (motherboard maybe?) or what?

But a word of caution, even within the T43 series, there are screws in different places. I had two on the front bezel top (near the light), but only three on the bottom of the front bezel.

Everyone should look closely for the black screw head covers so that you don’t overlook a screw. Otherwise you might crack the front bezel (or other plastic part) if you try to remove without a hidden screw still in place.