A31 reboot and 'touchy-ness'

[Hugh Chardon]

Hey all, I'm new to the forum, just not to board-level electronics. I recently traded for a set of A31p's. One of which boots (yay !) and the other for parts (parts R good) I noticed loading the 'good" one that if I touched or bumped the top plate, it DIED. I was able to restart, and finish loading the OS (Ubuntu- 9.0) on the HDD, but I bumped it three more times, and ...it DIES. Not abuse or dropping it, just the soft whack to set my hands on the plate and type.
Now, I'll add I have dismantled and remade this machine twice, new (to the machine) keyboard, top deck and power supply, and have yet to see this WITHOUT THE DECK INSTALLED. By that I mean I tapped on the CPU, GPU, reflowed the RAM slots, but when I mount the deck (either one) a slight bump kills it.
Anybody got any ideas ?

[rkawakami]

Welcome to thinkpads.com!

By "deck", do you mean the top plastic cover which surrounds the keyboard? If so, that's generally referred to as the keyboard bezel. I can't remember if there's a chance of any metal on that bezel to short with something else in the system the last time I had an A31p opened up. About the only thing that I can think of which could affect the running of the system is if the bezel is not properly aligned with the lid switch. That piece is to the left of the right hinge; it looks like a round, plastic button which sticks up through a hole. However, even if this is the problem, depressing the lid switch should either make the system go into standby or hibernate mode and not "die".

Are you running with a battery and an AC adapter?

[Hugh Chardon]

Correct...by 'deck' I mean whatever IBM/Lenovo calls it...
Battery (100%) So it will charge...and a NEW A/C adaptor marked for A31 plugged in.
BTW...lots of dust on this one...cleaned it, boy do these guys get dusty like this ?

[ajkula66]

First thing I'd do would be to take the CPU out and take a good look at it with a magnifying glass, or under a microscope.

Have you run PC-Doctor on it?

My assumption is that you have a crack somewhere on the planar.

Good luck.

[Hugh Chardon]

CPU under glass checks out...looked at the "keyboard bezel" (deck) and there is a small curl of copper cladding attached to the top near the USB and DC jack. It is slightly discolored. Can I modify/bend/remove this to further my troubleshooting? No warranty worries, just trying to keep Ground where it needs to be.

[rkawakami]

Without tearing down one of my own A31 systems, I'd guess and say that the copper piece is supposed to touch some metal on the base and thus provide either some RF or electrostatic discharge protection. You should be able to temporarily bend it back or cover it with electrical tape and see if that helps. Inspect the area under which that tab is touching the base and see if there's any kind of circuitry there.

[Hugh Chardon]

Without tearing down one of my own A31 systems, I'd guess and say that the copper piece is supposed to touch some metal on the base and thus provide either some RF or electrostatic discharge protection.

Yep, that was my thought. I insulated it, and re-installed the deck piece. thumped it a few times (to troubleshoot)
No ill effects. I'm thinking it was touching something it wasn't supposed to. Been using it now for 12 hours, offline and on, no dying.
Many thanks to you for the time you spent noodling on this, I sincerely appreciate your expertise.