Wikipedia:Reference desk/Archives/Computing/2021 February 12

= February 12 =

USB keyboard suddenly dead
Last night my USB keyboard (a fairly nice Kensington one, not a piece of junk) suddenly stopped working. It might have gotten jostled or something but it wasn't dropped on the floor or anything like that. It just seems dead: typing does nothing, caps and num lock LED's don't light, switching from one USB port to another doesn't help. I had another, less-nice keyboard around so am using that one now. I haven't done any electrical tests on the old keyboard. I do have a voltmeter so I guess I could open it up and test the cable connections, but the connector :::and strain reliefs look fine visually. Any idea what the typical failure modes are for something like that, and any troubleshooting tips? Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 22:14, 12 February 2021 (UTC)
 * At least try unplugging other USB things, as perhaps another ting is causing a problem. And then also powering the computer off and on might reset something to make it work. Graeme Bartlett (talk) 00:14, 13 February 2021 (UTC)
 * Hmm, the only other usb device plugged in is a mouse, and I did unplug that. I rebooted the computer but I don't think I fully power cycled it.  I guess I should do that.  I don't have another working computer to try the keyboard on, but I can plug it into a usb power bank and see whether the leds flash.  Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 08:05, 13 February 2021 (UTC)
 * Have you inspected and cleaned the inside of the USB plug? A slim pencil eraser can clean corrosion (be careful of schmutz) and a cotton swab with isopropyl (not rubbing) alcohol can also make a clean sweep of it. This is more common for mobile devices and those which are frequently unplugged and plugged back in, but it's at least worth a try here. Elizium23 (talk) 08:32, 13 February 2021 (UTC)
 * It looked fine, though I can check again. It is a full sized USB-A plug and it was plugged into the computer when the keyboard stopped working.  I'm a bit more suspicious of the wire inside the cable: maybe something came loose under the strain relief or something.  Checking it with a continuity tester will require opening up the keyboard so I'll have to get it together to do that.  2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 09:21, 13 February 2021 (UTC)
 * You do not say what kind of computer or OS you have, so we are guessing a lot here.
 * When you boot the computer, assuming you have a PC-type thing, it has a UEFI screen. Can you pause booting and enter the Setup utility, and then plug/unplug/replug the keyboard to see if it has any life?
 * Needless to say, have you tried it in another different host device??? Elizium23 (talk) 10:04, 13 February 2021 (UTC)
 * You can try fiddling with the cable around where it enters the keyboard. I've definitely had that work for mice, but also I think at least one keyboard. I think pushing the cable towards the keyboards may be most likely to help, but this is obviously pure anecdotal with no attempts to test what works. Nil Einne (talk) 13:53, 13 February 2021 (UTC)
 * Thanks everyone (this is OP), yeah I will try fiddling with the cable again. Computer is an old Thinkpad running Debian 10 but the thing is, swapping out the keyboard for another one worked just fine, so it doesn't seem like a software issue.  I didn't have another host device handy to try but will attempt that too when I get a chance.  For now I'm ok using the "new" keyboard.  (At least I didn't go buy another keyboard--it's just another old one that I had sitting around). 2601:648:8200:970:0:0:0:C942 (talk) 22:21, 18 February 2021 (UTC)
 * You can try fiddling with the cable around where it enters the keyboard. I've definitely had that work for mice, but also I think at least one keyboard. I think pushing the cable towards the keyboards may be most likely to help, but this is obviously pure anecdotal with no attempts to test what works. Nil Einne (talk) 13:53, 13 February 2021 (UTC)
 * Thanks everyone (this is OP), yeah I will try fiddling with the cable again. Computer is an old Thinkpad running Debian 10 but the thing is, swapping out the keyboard for another one worked just fine, so it doesn't seem like a software issue.  I didn't have another host device handy to try but will attempt that too when I get a chance.  For now I'm ok using the "new" keyboard.  (At least I didn't go buy another keyboard--it's just another old one that I had sitting around). 2601:648:8200:970:0:0:0:C942 (talk) 22:21, 18 February 2021 (UTC)