• Faulty keyboard on Lenovo laptop

    From Mike Clarke@21:1/5 to All on Fri Nov 25 15:21:10 2022
    I have a keyboard problem with a Lenovo Thinkpad which won't boot
    because it detects a stuck key. The error code implies that the
    offending key is the numeric 6 key but it's not physically stuck, I've
    prised off the keycap and the rubber dome underneath moves freely with
    an audible click so I'm assuming it's a short circuit problem inside the keyboard.

    I might be able to source a replacement keyboard but I'd like to check
    that there's no other problems with the laptop before doing that. I'm contemplating disconnecting the ribbon cables for the keyboard and
    plugging in an external USB keyboard for testing. Would this be likely
    to work and if not is there any danger that powering up the laptop
    without its internal keyboard could be harmful?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From jkn@21:1/5 to Mike Clarke on Fri Nov 25 08:34:17 2022
    On Friday, November 25, 2022 at 3:21:12 PM UTC, Mike Clarke wrote:
    I have a keyboard problem with a Lenovo Thinkpad which won't boot
    because it detects a stuck key. The error code implies that the
    offending key is the numeric 6 key but it's not physically stuck, I've
    prised off the keycap and the rubber dome underneath moves freely with
    an audible click so I'm assuming it's a short circuit problem inside the keyboard.

    I might be able to source a replacement keyboard but I'd like to check
    that there's no other problems with the laptop before doing that. I'm contemplating disconnecting the ribbon cables for the keyboard and
    plugging in an external USB keyboard for testing. Would this be likely
    to work and if not is there any danger that powering up the laptop
    without its internal keyboard could be harmful?

    99.9% sure that you can power up without the keyboard; and Thinkpads
    are about the best laptops to disassemble & remove the keyboard (unless
    it's a pretty modern one; I have a T14s with a keyboard problem which
    looks like a pain in that regard)

    What you suggest is exactly what I would try.

    J^n

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Mike Clarke@21:1/5 to jkn on Sat Nov 26 12:42:18 2022
    On 25/11/2022 16:34, jkn wrote:
    On Friday, November 25, 2022 at 3:21:12 PM UTC, Mike Clarke wrote:
    I have a keyboard problem with a Lenovo Thinkpad which won't boot
    because it detects a stuck key. The error code implies that the
    offending key is the numeric 6 key but it's not physically stuck, I've
    prised off the keycap and the rubber dome underneath moves freely with
    an audible click so I'm assuming it's a short circuit problem inside the
    keyboard.

    I might be able to source a replacement keyboard but I'd like to check
    that there's no other problems with the laptop before doing that. I'm
    contemplating disconnecting the ribbon cables for the keyboard and
    plugging in an external USB keyboard for testing. Would this be likely
    to work and if not is there any danger that powering up the laptop
    without its internal keyboard could be harmful?

    99.9% sure that you can power up without the keyboard; and Thinkpads
    are about the best laptops to disassemble & remove the keyboard (unless
    it's a pretty modern one; I have a T14s with a keyboard problem which
    looks like a pain in that regard)

    What you suggest is exactly what I would try.

    J^n

    Thanks. I removed the keyboard and connected an external USB keyboard
    and everything worked fine.

    Then I shut down, unplugged the USB keyboard and reinstalled the
    internal keyboard and was surprised that the BIOS no longer reported a
    stuck key. I think there's more to this than being cured by just
    reseating the ribbon cables because I'd done that previously with no improvement but this is the first time that I'd powered up the laptop
    without the keyboard so I'm wondering if the stuck key state was latched
    in the keyboard driver until it found no keyboard there.

    I'll keep my fingers crossed and hope the problem doesn't return.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)