Issuse with few keys of internal laptop keyboard.

iamokish · 2024-05-27 06:13:09

I'm encountering a perplexing issue with my laptop's keyboard that I'm hoping anyone can assist me with.

Around 5-6 months ago, I set up a dual boot system on my laptop, running Arch Linux alongside Windows 11 using GRUB (with Secure Boot disabled). Initially, everything worked seamlessly. However, after about a week, approximately 30% of my keyboard keys suddenly stopped functioning. These keys remained unresponsive across all operating systems (Linux, Windows), as well as in BIOS and GRUB. Even after reinstalling both operating systems from scratch, the issue persisted, leading me to suspect hardware-related issues such as dust or moisture.

To resolve the problem, I replaced my laptop's keyboard with a new one. This seemed to solve the issue. Now fast-forward to last week, I installed arch again. Again, initially everything worked seamlessly, but to my dismay, the same keys that were malfunctioning previously stopped working again after a few days. Once more, these keys were unresponsive across all environments - Linux, Windows, BIOS, and GRUB.

I altered the boot priorities in my BIOS, setting Windows Boot Manager as the first priority and enabling Secure Boot to facilitate gaming in Windows. Although I later disabled Secure Boot, Windows Boot Manager remained the first priority. Surprisingly, the next day, the previously malfunctioning keys started working again without any apparent intervention on my part.

Any guidance or assistance you can provide in resolving this matter would be greatly appreciated.
Please let me know if any further information is required.

Keys that are not working:-

White = Working
Grey = Not Working

Device Info:-

System:
  Host: kyusou Kernel: 6.9.1-arch1-2 arch: x86_64 bits: 64 compiler: gcc
    v: 14.1.1 clocksource: tsc avail: hpet,acpi_pm
    parameters: BOOT_IMAGE=/vmlinuz-linux
    root=UUID=6dc241f4-x9xx-4520-x2x2-142f203e272x rw loglevel=3 quiet
  Desktop: KDE Plasma v: 6.0.4 tk: Qt v: N/A info: frameworks v: 6.2.0
    wm: kwin_x11 vt: 7 dm: LightDM v: 1.32.0 Distro: Arch Linux
Machine:
  Type: Convertible System: LENOVO product: 82HU v: FLEX 5 14ALC05
    serial: ****************** Chassis: type: 31 v: FLEX 5 14ALC05
    serial: ******************
  Mobo: LENOVO model: LNVNB161216 v: SDK0Q55722 WIN
    serial: ****************** part-nu: LENOVO_MT_82HU_BU_idea_FM_IdeaPad
    Flex 5 14ALC05 uuid: ****************** UEFI: LENOVO v: GJCN33WW
    date: 08/29/2023
CPU:
  Info: model: AMD Ryzen 7 5700U with Radeon Graphics bits: 64 type: MT MCP
    arch: Zen 2 gen: 3 level: v3 note: check built: 2020-22
    process: TSMC n7 (7nm) family: 0x17 (23) model-id: 0x68 (104) stepping: 1
    microcode: 0x8608104
Graphics:
  Device-1: AMD Lucienne vendor: Lenovo driver: amdgpu v: kernel arch: GCN-5
    code: Vega process: GF 14nm built: 2017-20 pcie: gen: 3 speed: 8 GT/s
    lanes: 16 link-max: gen: 4 speed: 16 GT/s ports: active: eDP-1
    empty: HDMI-A-1 bus-ID: 04:00.0 chip-ID: 1002:164c class-ID: 0300
    temp: 38.0 C
  Device-2: Generic Integrated Camera driver: uvcvideo type: USB rev: 2.0
    speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 1-4:3 chip-ID: 174f:243f
    class-ID: 0e02 serial: 200901010001
  Display: x11 server: X.Org v: 21.1.13 with: Xwayland v: 24.1.0
    compositor: kwin_x11 driver: X: loaded: amdgpu unloaded: modesetting,vesa
    alternate: fbdev dri: radeonsi gpu: amdgpu display-ID: :0 screens: 1
  ....
  ....
USB:
  Hub-1: 1-0:1 info: hi-speed hub with single TT ports: 4 rev: 2.0
    speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 chip-ID: 1d6b:0002
    class-ID: 0900
  Device-1: 1-4:3 info: Generic Integrated Camera type: video
    driver: uvcvideo interfaces: 2 rev: 2.0 speed: 480 Mb/s (57.2 MiB/s)
    lanes: 1 mode: 2.0 power: 500mA chip-ID: 174f:243f class-ID: 0e02
    serial: 200901010001
  Hub-2: 2-0:1 info: super-speed hub ports: 2 rev: 3.1
    speed: 10 Gb/s (1.16 GiB/s) lanes: 1 mode: 3.2 gen-2x1 chip-ID: 1d6b:0003
    class-ID: 0900
  Hub-3: 3-0:1 info: hi-speed hub with single TT ports: 4 rev: 2.0
    speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 chip-ID: 1d6b:0002
    class-ID: 0900
  Device-1: 3-3:3 info: N/A type: <vendor specific> driver: N/A
    interfaces: 1 rev: 2.0 speed: 12 Mb/s (1.4 MiB/s) lanes: 1 mode: 1.1
    power: 100mA chip-ID: 06cb:00be class-ID: ff00 serial: 96bb6a669720
  Device-2: 3-4:4 info: MediaTek Wireless_Device type: bluetooth
    driver: btusb interfaces: 3 rev: 2.1 speed: 480 Mb/s (57.2 MiB/s) lanes: 1
    mode: 2.0 power: 100mA chip-ID: 0489:e0cd class-ID: e001 serial: 000000000
  Hub-4: 4-0:1 info: super-speed hub ports: 2 rev: 3.1
    speed: 10 Gb/s (1.16 GiB/s) lanes: 1 mode: 3.2 gen-2x1 chip-ID: 1d6b:0003
    class-ID: 0900
Info:
  Processes: 301 Power: uptime: 8m states: freeze,mem,disk suspend: deep
    avail: s2idle wakeups: 0 hibernate: platform avail: shutdown, reboot,
    suspend, test_resume image: 5.97 GiB services: org_kde_powerdevil,upowerd
    Init: systemd v: 255 default: graphical tool: systemctl
  Compilers: gcc: 14.1.1 Shell: Bash v: 5.2.26 running-in: konsole
    inxi: 3.3.34

Last edited by iamokish (2024-05-29 06:52:21)

seth · 2024-05-27 08:09:01

Please use [code][/code] tags, not "quote" tags. Edit your post in this regard.

keys remained unresponsive across all operating systems … the same keys that were malfunctioning previously stopped working again … keys were unresponsive across all environments … the next day, the previously malfunctioning keys started working again without any apparent intervention on my part

The pattern in your illustration is geometrc, not logic, so this is most likely a HW issue.
Temperature and tension look like they could be a thing (ie. the keyboard bends and that breaks the signal paths)
The old keyboard might just as magically still work (again) - can you operate it outside the case (the connector cable is probably very short, but maybe you can lift it and put a stable cardboard or thin plywood underneath?)
Can you operate the system in a climate controlled environment?

Unfortunately in that case any kind of HW fix will require some local inspection of the situation (and coming up w/ a plan where to wedge some paper for support or take off some plastic and of course the impact of that on case-temperature management - you cannot just shove some paper somewhere inside a notebook and expect that to have no impact on the air-flow…)

iamokish · 2024-05-29 06:56:32

Thanks for your response and for offering insights into potential hardware issues. However, after further testing, I can confirm that environmental factors like temperature and tension don't seem to be the root cause. I've tested the keyboards in various environments, including controlled climates, and they functioned without any issues outside of the laptop case.

Additionally, there were no observable bends or tension on the keyboard during these tests. Both the old and new keyboards worked flawlessly when operated outside of the laptop case.

It seems that the problem specifically arises within the context of the laptop's internal setup, as the keyboards function perfectly when connected to other systems or used outside of the laptop casing. Therefore, it's likely not a hardware issue related to temperature or tension but rather something specific to the laptop's configuration or environment.

Any further suggestions or insights would be greatly appreciated.

seth · 2024-05-29 08:14:54

Temperature and tension would be related to the case anyway, the keyboard might be wedged into the frame and start to bend or rest over some hot spots.
Also the connector cable might "break" on folding or resting on a hot spot, but you'd probably not get the consistent failure patterns if it was the signal.

The fact that it strcitly related to the keyboard inside the frame actually proves that it's HW related - can you
a) sense hot areas where the broken parts of the keyboards would be?
b) flex the keyboard by pressing on the center or either of the sides when it's mounted in the case?

ewaller · 2024-05-29 15:18:45

Or shorts. is there any place where traces on the keyboard could short to any metal in the laptop chassis? Some (crappy) designs depend on the solder mask over traces to provide insulation. It can chip, peel, or be abraded from the surface of a PWB and the copper underneath can be exposed. It is also not impossible that surface mount parts near the edge of a board could touch the chassis. https://resources.pcb.cadence.com/blog/ … iderations

Kapton tape can be a life saver. https://en.wikipedia.org/wiki/Kapton
https://www.amazon.com/kapton-tape/s?k=kapton+tape

Arch Linux

#1 2024-05-27 06:13:09

Issuse with few keys of internal laptop keyboard.

#2 2024-05-27 08:09:01

Re: Issuse with few keys of internal laptop keyboard.

#3 2024-05-29 06:56:32

Re: Issuse with few keys of internal laptop keyboard.

#4 2024-05-29 08:14:54

Re: Issuse with few keys of internal laptop keyboard.

#5 2024-05-29 15:18:45

Re: Issuse with few keys of internal laptop keyboard.

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