T43 monitor not working correctly - screen blank

[pkd]

Hi,

I have a T43 and its monitor stopped working correctly. It shows up a quite black - I can still see some windows on the monitor very lightly, but I can not see the mouse. I tried to increase the brightness but that did not help.

I had changed the left hinge on the laptop about 3 weeks ago (so I had opened up a lot of parts), and since then the colors seemed to be a little off. That was still OK, but now, I am not getting any visibility on the screen.

Please help.

Thanks
pkd

[virge]

Here's what I would do:

1. Check to see if the lid switch is stuck.
2. Plug in external monitor to see if the colors are still "off."

If it shows up fine on your external then you likely have a problem with the backlight or inverter. Try checking the cables to the inverter next.

[SteveS]

When the "colors seemed to be a little off", were they too red or whites looking pink? If so, your backlight lamp was dying and has died. It is possible that this is an inverter problem, but not likely.

First check the connections to the inverter. The high voltage connections to the lamp have a dedicated connector with the pins spaced further than normal. It these are OK, try swaping the inverter. It is less effort to replace and should be less expensive than replacing the display. The inverter does have a dedicated power supply fuse on the system board, but if it failed you would not have experienced color shifts before it went.

While some members have reported success in replacing the lamp only in a display assembly, it is very difficult. Lenovo only supports replacement of the entire display "sandwich" assembly when the lamp dies. I tried this once, and found I could not properly replace the reflective tape to get even background illumination - the display had lighter areas in it.

[pkd]

These are my observations from last 3-4 days. The light came back on twice on its own, and went off once. I am not sure whats going on. This problem is intermittent.

If I connect to external display, the colors are fine.

I am not exactly sure what is lid switch. I think it is a switch which gets pressed when we close the computer. I checked it is correct, and I could manually press it which caused the computer to go into standby mode.

Looking at the thinkpad manual, it says that if the lcd screen is too dark, then reseat the lcd connectors. Should I try this ?

It looks to me that this thing is caused by some screwup I did while replacing the hinge (this was my first time). If I remember correctly, around the lcd connector, the original screw did not work correctly, and I had to use a bigger screw to tighten it. I am not sure if it has something to do wit that. Further I was not very sure of how two wires coming out of LCD (for the mini pci adapter) into the main unit - how are they supposed to come in. I did not remember it correctly when opening (forgot to take picture), and had problems getting it back into the main unit. I got it in, but I am not sure if it is the correct way. Is there way to figure out what is the correct way ? Thinkpad manual was not very informative.