[SOLVED] Faulty trackpoint on x220 (intermittent; no success with hardware replacement)...

[dafreedm]

Hi all,

Longtime reader of this forum (10+ years), but infrequent poster. I have a Thinkpad x220 with problems with the Trackpoint (red mouse controller in center of keyboard), as well as associated three mouse buttons under the keyboard's space bar. The Trackpad (along with its integrated buttons) works fine. I believe this is a hardware issue, but I'll explain further...

(1) It's intermittent in terms of working / non-working, but it only changes from working to non-working, or back again, after either system reboot, or system recovery from hardware suspend (S3 state). So, that suggests to me some form of initialization going wrong.

(2) When it initially stopped working, no O/S settings nor BIOS settings had been changed. It just stopped working (though since has worked, and not worked).

(3) It exhibits same intermittent wokring / non-working problem in both Linux (typical O/S on laptop) as well as with Win10 (occasional laptop usage).

(4) On even rarer times, it's worked "incorrectly", rather than not at all. In such times, the sideways function of the trackpoint works correctly, but the up/down directions are reversed. In other words, pushing trackpoint up, makes cursor move down; pushing trackpoint down, makes cursor move up. Weird! At the same time that this is happening, the trackpad works completely correctly.

My immediate thought was that this was a hardware issue, and I ordered a replacement keyboard / trackpad module (genuine new lenovo FRU). However, the problem has persisted, and I've already tried two replacement boards. This makes me wonder if there's not an underlying hardware issue on the main system board, but that would be a real shame given the cost and hassle involved of replacement.

I've searched all over online for more info on this but haven't seen any other descriptions of it.

Any suggestions from the Thinkpads.com community would be great help!

Take care...

[thinkpadcollection]

Start diagnosing by trying one memory at a time, change processor, even leaving out wireless card, bluetooth module, etc. Also disable one item at a time in security settings for the ports and hardware, don't need to set password.

trackpad and trackpoint are usb interfaces and might be conflicting with another software item or hardware add on non-thinkpad items?

Cheers, thinkpadcollection

[dafreedm]

Hi,

Thanks for the suggestion. However, I can't understand how that potential diagnosis would match two of the symptoms:

(1) It started all of a sudden after years of successful use, without any other change of hardware or O/S. If the O/S were just Windows, maybe windows did some behind the scenes update which caused the problem. But, Linux (at least my distro) doesn't do updates without user intervention, so that doesn't seem to fit.

(2) The issue is intermittent, in that it sometimes works perfectly after reboot, and other times it doesn't work at all.

Could you please explain how your recommendation fits with these symptoms? If there really is a USB conflict, shouldn't I see that conflict either ALL of the time, or none of the time? I really appreciate the input, just don't understand how they fit my situation.

Thanks again.

[axur-delmeria]

Try disconnecting the touchpad. The trackpoint and touchpad share the same PS/2 port, and if one misbehaves, the other is affected.

[dafreedm]

Axur --- thanks for the suggestion. I'll try that and let you know what I find...

[dafreedm]

It took me awhile to try it out, but I did and it now works perfectly (at least for the few times I've since rebooted the laptop). I'll repeat what I did for others to make it more clear: I removed the keyboard for my Thinkpad X220 (with its embedded Trackpoint). I then removed the wrist rest with its embedded trackpad and fingerprint reader, both connected via the same flexible PCB-cable, to the motherboard. I disconnected that cable (from the rear-side of wrist rest), and then reassembled the machine, leaving the Trackpad (and fingerprint reader) disconnected. I rebooted and now the TrackPad seems to work reliably.

A BIG thank you to axur-delmeria --- I've been trying to solve this for the better part of half a year!