Keyboard problem on a ThinkPad 760L

Hello everybody.

I got a few days ago the model ThinkPad 760L with a few issues. The first one was a bad 810MB drive, for which I purchased a 2.1GB one and so far so good.

Now, when I received the notebook the keyboard was working fine. Boot the notebook today and I can’t use any keys other than the function keys and the six-key group (PgUp, PgDn, Ins, Home, Del, End). And also, they have their Fn hold stuck. What I mean with this is that normally a function key needs to have held the Fn key to perform special functions on a computer, like save to RAM, a teen to VGA, Battery read, etc. But now I just press the funcion keys and the corresponding function is performed.

Can this mean just a keyboard issue, for which if so I do have a replacement saved in my bookmarks? Or it is worse, like a problem with the system board not recognizing the keyboard presses properly?

I hope to read your comments.
Thank you very much in advance for your answers.

Comments

  • Maybe it's either bad contacts inside the laptop (where the keyboard connects to), or there might be sticky residue inside the keys themselves.

  • Try re-seating the connector, disassembling, cleaning, and re-assembling the keyboard.
    You know, the usual stuff.

  • Already tried those tips and still no go. Must be something I screwed up during the hard disk swapping at the moment.

    Anyways, I have an external keyboard and it works perfectly, so I will order a spare hard drive and a keyboard assembly soon. Thank you very much both of you for your help.

  • edited May 17
    The resume battery (located under the palmrest) may have leaked, and if so, had damaged the keyboard card, which I believe is what causes the keyboard inputs to register incorrectly. I know that because it has happened to 3 of my 4 760EL/EDs*.

    *More specifically, both my Singaporean 760EL and 760ED have had severe corrosion and would go to sleep while starting Windows (because the corrosion had gotten so bad that it keeps thinking the keyboard lid is always open), and my US 760ED has corroded keyboard and TrackPoint button connections but otherwise does work. My US 760EL works perfectly as I was able to remove the resume battery before it was able to corrode a significant portion of the keyboard card. (I can tell them apart because the Singaporean ones were "Made in Japan", while the US ones were "Made in Mexico")

    The keyboard input issues are the early signs, and eventually the TrackPoint buttons will stop working, then it'll eventually keep thinking the keyboard lid was always open and thus would fail to boot once protected mode drivers load.

    (Addendum: I came here from a Web search and just wanted to point out the IBM ThinkPad 760 series resume battery leakage issue symptoms for anyone else who may be experiencing it. I just wish for a way to repair the corroded keyboard cards (yes, "keyboard card" was the official term for the PCB located under the palmrest as described by the IBM HMM for this series), which is something I'm trying myself, but it would be incredibly daunting for me to do)

    (Addendum 2: If I recall correctly, the resume battery was originally intended to keep the RAM powered when the OS signals the hardware to go to sleep or suspend to RAM, so the batteries could be swapped, and those went away once Windows gained built-in hardware hibernation (suspend to disk). However, (IIRC) batteries used for those were often NiCd batteries, sometimes NiMH, which would eventually grow dendrites that then grow along the wires and onto the PCBs, causing corrosion. Just putting that out there for those who are curious)
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