ThinkPad T61 Problem - Display

[ll357355]

I have a thinkpad T61, and the Display gets very very dim and the color becomes weird.
Sometimes the display turns off...

any thoughts on what may need to be replaced or fixed?

Thx!

[sktn77a]

Could be a variety of things but sounds like a failing backlight (although these usually take 3-5 years to fail). I take it you are no longer under warranty?

[ll357355]

correct-no warranty.

can a backlight be replaced, or is it the LCD screen itself?

[sktn77a]

The backlight (a pencil-like fluorescent tube or CCFL) can be replaced but it's a fiddly job. Several forum members have replaced them but its not something I would try. You can get a complete lid (with LCD, CCFL, etc) for a reasonable cost on e-bay. Might be the easier way to go. Just make sure you get the same one. Alternatively, you may be able to upgrade to a higher resolution, if you would like that, but you may need additional parts (inverter, etc).

[rkawakami]

<snip>.. the Display gets very very dim and the color becomes weird. Sometimes the display turns off...

Could also be a ribbon cable. Here's a quick list of things that can go wrong with video issues:

- LCD panel; there's a defect within the panel itself - usually evident by dead column(s) and/or row(s) of pixels
- backlight (CCFL); the florescent tube inside the LCD panel which provides the white light inside the LCD
- LCD ribbon cable; routes the video signals to the LCD panel and power to the inverter
- inverter; loss of backlighting (brightness) - the inverter board powers the CCFL tube
- lid switch; controls power to the inverter board
- motherboard; various things can fail - graphics processor (GPU), power, etc.

Dimness can be the CCFL, the ribbon cable, inverter or lid switch. Weird colors can be an aging CCFL (pink or red tint, usually more evident when the display is turned on after being off for some time or the brightness control is at the minimum setting), a bad ribbon cable or a problem with the LCD panel.

Does flexing and/or moving the lid assembly make the problem appear or go away? If so, that tends to indicate an intermittent connection is causing the problem. That can be the ribbon cable, where it plugs into the motherboard or the back of the LCD or there's a crack somewhere in the cable in between those two points. If both the video distortions (colors or image on the display) and the loss of brightness occurs at the same time, I would think that there's a problem with the ribbon cable. Specifically, where it plugs into the motherboard (re-seat the connector; pull it out and then push it back in) or there is a break in the cable (closely inspect the entire length, especially at the areas where the cable bends or twists).

The Hardware Maintenance Manual has all of the instructions on how to take the system apart:

http://www-307.ibm.com/pc/support/site. ... 39298.html (Main HMM index; find the T61 model type you have)