T20 Video Problem

[jruschme]

A few months ago, I inherited a T20 which was being retired by my employer. Everything was fine until recently when its hard drive failed. I installed a replacement and reloaded it with XP Pro. Since then, I've been having intermittent video problems.

Randomly, the LCD will randomly lose contrast and brightness. The screen is still readable, but the overall effect is that I am now looking through a blue-grey mesh. Just as randomly, the screen will pop back into its normal bright self. (It just did that as I was writing this.)

I can't seem to find a set of actions to repeat the problem, though I have noticed it occuring after moving or readjusting the system. This makes me think that I might be looking at a loose connection or failing cable. However, I can't seem to duplicate the problem just by waggling the screen or randomly tilting the entire TP. Operating on AC or battery doesn't seem to affect the problem.

So, has anyone else seen something like this before? Any advice on what I can do to fix it?

Thanks...

[tfflivemb2]

I agree, I would check the connections first. You can use the Hardware Maintenance Manual to show you how to get to the connectors to check them.

Let us know what happens.

P.S. Welcome to the forum!

[mattyprice4004]

In the long run, if checking the connections doesn't work, I would suspect perhaps the inverter or the CCFL fluorecent backlight.

The backlight on my 600E has completely failed before now, a new inverter solved the problem.

If the screen had a noticeable pink/yellow tinge before failing, that to me would indicate a backlight tube failure, not the inverter.

Mat

[jruschme]

So, I finally decided to open the T20 up and see if the intermittent video problem was a loose connection... and wish I hadn't.

For a while, the problem had seemed to go away. Then, while on vacation, it started with a vengence- lots of going in and out of the "blue grey" mode, but always coming out of it. The incidents seemed to be more frequent, particularly if I had just moved the ThinkPad (as in putting it on the coffee table when getting up from the couch). The frequency got to the point, though, where I decided to open it up on Monday.

I could find no loose connections, but in the process of reassembly, broke the "rotating" cable shield in the lid. On first startup, it seemed to start fine, but as soon as the inverter kicked to full brightness, the grey overcast came back... and hasn't left, despite several reboots and even being turned off for a time.

I'm still open to suggestions... I'm suspecting a failure within the flexible cable, though I'd also need to replace the guide/shields that I broke.

Anybody got a cheap T20 lid assembly with cable, but minus LCD?

[Kaervak]

It sounds like your inverter is going. Since you said the LCD ribbon seems ok, the inverter is the only other likely option. Thankfully they're not all that hard or costly to replace. eBay, IMO, is your best bet to find a cheap replacement.

[jruschme]

Well, I finally took a brute force approach to the problem... I was able to obtain a dead T20 (usual startup problem and, no, none of the usual resolved the problem) with a good screen and swapped the tops of the two.

While taking the "good" one apart to remove the LCD assembly, I removed the keyboard bezel (which I hadn't done before) and discovered that the actuator for the lid switch had broken loose from the bezel and floating around inside. (Funny, but I never heard it rattle.)

In the end, I did a "best of breed" reassembly which included a known working LCD and intact lid switch. I'm left wondering, though, if my original problem was not with the cable or the inverter, but with a loose piece of metal grounding something out (S-Video connector, perhaps?). At the point where I discovered the broken actuator, though, I was so far involved that all I wanted to do was put the one back together.