T43 Keyboard and Touch Pad not working

[jsailorca]

Hi,

I have issue with my T43 keyboard and touchpad not working after working on the computer for a while. I suspect this is a motherboard issue. Is this relating overheating to the ATI GPU or the chip which is located directly north of the GPU and right of the CPU (when the screen is facing you)? Specifically, is it the GPU or the other chip. Thanks for the help.

[ajkula66]

That sounds like a textbook example of the failing SouthBridge chip - which is the big square one right under the wireless card - and you can test it by pressing (gently) on it when the machine is frozen, to see whether the keyboard comes back.

You'll likely need a new motherboard, I'm sorry to say.

[jsailorca]

That sounds like a textbook example of the failing SouthBridge chip - which is the big square one right under the wireless card - and you can test it by pressing (gently) on it when the machine is frozen, to see whether the keyboard comes back.

You'll likely need a new motherboard, I'm sorry to say.

I didn't know there is another big chip under the Wifi card. Is it possible to reflow it via "aluminum foil" + "heat gun" method or use a cut out metal sheet like the link stated below?

http://www.thinkwiki.org/wiki/How_to_bu ... dge_cooler


Think it's worth a try or am I out of luck?

[ajkula66]

You can't reflow a SouthBridge chip. It must be re-balled.

[RealBlackStuff]

I wouldn't bother, you run a 98-100% chance to ruin it.
For $45.- you get a brand new mobo with ATI X300 GPU: http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 1166355747

[jsailorca]

That sounds like a textbook example of the failing SouthBridge chip - which is the big square one right under the wireless card - and you can test it by pressing (gently) on it when the machine is frozen, to see whether the keyboard comes back.

You'll likely need a new motherboard, I'm sorry to say.

Thank you RealBlackStuff and George. I am buying a mobo. FYI, I gently pressed on the SouthBridge but didn't have any effect. Oddly enuff, I removed the protected cable connecting between the trackpad and the board and thing started to work again. Maybe it's the heating of the connect by the ATI chip (as the cable was hitting the heatsink of the ATI (but not appreciably hot though).

[ajkula66]

So try using it with the touchpad disconnected for a bit and see if the keyboard behaves normally...you may end up needing a new palmrest instead of the board...doesn't hurt to try...

Good luck.

[automobus]

Two people reported individual T43 where: pointing devices do not work while trackpad attached, TrackPoint does works when UltraNav trackpad removed.

T43 touchpad malfunction

Your case is different: you say keyboard stops working, too. But if you find your ThinkPad to be perfectly reliable without connected trackpad, then consider adding your voice to the other discussion. (It helps us all, to be able to count instances in one place, rather that scattered reports all over the place.)