600E display problem (black screen)

[fje]

Hi,

as some of you already know I was upgrading my 600E and in terms of processor and memory, everything went OK, but in one of first dissasemblies I feel i damaged something that made the laptop display unusable.

Following what I found in this forum (the "gosht light" from the right hand of the display could be seen), I felt the problem could be the right hand cable to the screen.

So I bought a set of screen cables and changed the right hand one.

Initially the problem seemed to stay in the same situation (I thought about a bad Fn+F7 combination too late ). I tried to change again the cable and also the left hand one, but same result.

And suddenly, in one of the tests, the screen stayed black, no "gosht light". I tried all the combination of the cables, but no luck....

Now is when I thought about the Fn+F7 combination.... too late, I said....

I tried if the display lid switch could be bad, but it seems to be working, because when I open or close the display having an external display connected, the external monitor switches on or off and I need the Fn+F7 combination to have it again on... so the switch seems to work (and the graphics are there... in the external monitor).

Then I thought that maybe the inverter card or the CCFL light itself could be damaged this time. I bought an inverter card and a CCFL light... Got them and tried this weekend....

Same result . Black screen, no "gosht light".

Of course I unplugged and re-inserted the cables in its connectors.

So, what can be the problem? I cannot find any ither source of the problem. Is there any way I can test something to find (or eliminate) the source of the problem? (Of course I don't have other 600E to interchange things...)

Thanksfor any idea.

[Laptoplucknow]

Hey FJE: Have you ran the PC doctor utility that is available on the IBM website? It has multiple screen test functions. Did you test the back-light before you did the replacement? The back light in one of my 600Es went red before it died. It still lit up when tested but not when it was in the machine. A new/used back light fixed the issue. Good luck!

[fje]

I feel the PCDoctor is not a solution, as the screen is TOTALLY black.

And I didn't test the backlight before installing it, I assumed it was OK. BTW is there any way that I could check the backlight without connecting it to the inverter card? For instance, with an ohmeter....?

[u.mac]

You may do a very short test with another inverter (from PC neon string/tube or PC-LCD-screen) - but be careful the inverter puts out >12.000v~.

[fje]

u.mac, thanks, but this is the reason I bought a new inverter card and it doesn't work too... I don't fell the new one I got is also bad....

Is there anything "before the inverter card" I could test if it is working or not.... ?