T42 backlight/screen problem

[mlinchits]

I have this issue where the screen on my t42 stays lit for about a minute after which the backlight powers off. The backlight turns on again for another minute after powering off the screen for a couple of seconds. You can still see the shapes on the screen when it goes dark.

I am assuming the screen itself is fine since it can be made to function properly for a minute after powering it off and on. Does anybody know where the problem lies and how to fix it?

Thanks

[rkawakami]

Welcome to thinkpads.com!

I can point you to this conversation that's currently running here in the T4x forum:

http://forum.thinkpads.com/viewtopic.php?f=2&t=76764

as that person also seems to have the same type of problem. If you reduce the brightness of the display (Fn+End), does it appear that it stays on a little bit longer? If so, then your problem may lie in a defective inverter board, an aging backlight inside the LCD panel or some other problem with the motherboard. The easiest and cheapest thing to do would be to replace the inverter board with a known working unit and see if that helps. Those boards usually run around $15 (shipped) off of eBay. In order to tell you the correct part number, you will need to supply us with the seven character TYPE number from the bottom of the system (e.g., 2374-ABC). It's also a good idea to put that TYPE number in your signature field here in the forum so that way people can see what your system configuration is and therefore provide better answers to any of your questions.

If you (or somebody you trust) are going to work on the system, then I would suggest first downloading a copy of the Hardware Maintenance Manual for the T4x systems from here:

http://www-307.ibm.com/pc/support/site. ... MIGR-46464

It has all of the instructions for taking apart the system.