possible solve of T43"usb power surge"/flex proble

[copperbird]

Hello

I am writting this message in the hope that the "usb power surge error" and other "flex issues" are solved this way. I don't know if this problem shows at every T43 system boards or only at some of them, but here is my story:

A few days ago, while I was searching for a sollution to solve the "strange noise problem while running on battery" problem, I found a possible sollution here, to press some piece of hardware to reduce vibrations and thus to reduce the noise.
The only problem was that the solution was described for an IBM T42, but I have an IBM T43, so the motherboard layout is not the same.
After I assembled the laptop again, dissapointed, I found the following error message when booting into windows: "USB Power surge error". Frustrated, I dissasembled the laptop again, then I powered it on and the message was gone. Then I re-assembled the laptop, and the message was still there, but showed up less frequently (especially if I pressed te palmrest just below the bottom-left edge of the keyboard).
Once again, I put the screwdriver to work and I removed the cover part of the laptop. I found out that if I press the cooling system, the message popped up. I removed the fan assembly and pushed on the motherboard edge - still the same message. Then I removed the PCMCIA cage and the problem persisted. Of course, while doing all these, I had the laptop powered down - I only powered it up to see if the message still appeared.

I thought that the metal under the board is not insulated properly, so because of the pressure, the board itself does this short circuit, so I mounted some very thin transparent plastic foil underneath, but this didn't solve the problem.
Then I took out every piece form the laptop case, put it on the table, re-attached the screen (and other vital components) to the mainboard and powered it on. Victory! No "usb surge" message! I flexed the board a little while running - no problem at all!

I put all the pieces together thinking the problem was solved and when powered it on - bummer! the samme message popped up on the screen.
I searched the forum and found out that it could be a "flexing problem", though the laptop was new and I don't take it by only one corner, neither when powered on, nor when powered off.
Then once more I dissassembled the laptop leaving an empty case, and when I analysed the situation better... what do you know... I found out that some connectors have no insulation underneath. These connectors are located on the right edge: the CD-ROM IDE connector and another connector above it. I have the 15 inches model (2669) and the board has some sort of adapter that makes these two connectors longer. So the insulation covered exactly the area under the board, but not the area under that adaptor (which is some sort of a "plug-in" card that mounts itself exactly on those two connectors, and thus makes the board wider by an inch, leaving another two identical connectors at its right edge - I am very sorry that I cannot explain this better, but my english is poor).

So, what I made was this: I put some thick (1 mm) transparent plastic foil under these connectors for insulation, and fixed this foil with some adhesive tape (I think it's called scotch tape). Then, to be sure there will be no more problems, I put another rectangle-shaped foil made of the same material underneat the bottom-left corner of the system board (under the pcmcia sockets). This foil was larger, so I punched some holes in it to make enough space for the screws. I left it rectalgle-shaped because it was very hard to cut it off after fixed it due to its thickness, so it lays also under a half of the cooling fan.

I reassembled the laptop for the final time (if this wasn't solve the problem, I would gave up), and fortunately, the problem was gone. Now I can press on the bottom-left corner of the palmrest and no more "usb power surge" error messages.
I hope this way others will solve similar problems.

Thank you for reading this long and boring message, and please don't blame me if you broke your laptop :p

PS: sorry, but I have no photos, and there's no way I will open up the laptop again to take some.

[christopher_wolf]

Welcome to the Thinkpad Forums

Thanks for that very detailed explanation of everything you did to solve that problem.
Do you think this happens on 14.1" models as well? I can imagine where the extenders on the connectors would leave some areas exposed.

[copperbird]

I don't know if this happens on 14.1" models, I dind't have one (except for my earlier T42 which was a 14" model), but I believe the "raw" motherboard is for the 14" models, and the extender is only necessary for the 15" models, because otherwise the CD-ROM wouldn't reach the motherboard IDE connector due to the fact that 15" models are wider than 14" ones.

But remember, this is only a supposition, I don't really know if motherboards for 14" models have that extender or not, but even if they haven't, on 14" models there may be other places that are not insulated as they should.

[bill bolton]

Do you think this happens on 14.1" models as well?

Since they don't need/use the connector extension piece, it seems highly unlikely.

Cheers,

Bill

[copperbird]

As I already said, I don't know if 14.1" models use the extension piece or not, it is only a supposition.

I would like to know if others managed to solve this problem in this way as well.