Weird keyboard problems....

[Joshua Judson Rosen]

On 02/07/2016 07:32 AM, Mark Komarinski wrote:
> You can isolate it by plugging in a USB keyboard and seeing if it
> still happens.  My guess is you're correct that it's a mechanical
> problem with the keyboard. Depending on the laptop model you have,
> purchasing a new one probably won't cost much (the ones I got were
> under $20) and replacing it is usually easy.  YouTube will likely
> have a video covering it.

Yeah. USB keyboard does in fact work fine. Actually, I'm confident that
it's not an OS-or-higher problem because I the symptoms even manifest
before the OS is booted--in the GRUB and even BIOS screens. I guess it
could be a keyboard controller problem, which would really suck if
that meant it was a mainboard issue instead of a keyboard issue per se....

It's a ZaReason (really a Pegatron B14Y, which ZaReason sold as
the UltraLap 430); i.e.: whitebox laptop, so it's especially straightforward
to disassemble. I've removed the keyboard a couple of times, now--
shaken it, tapped it on the table, tried blowing it out with canned
`electronics duster'. Swabbed the contacts on the connector with alcohol.

Those approaches `seemed to do the trick' for either minutes or hours,
which I'd guess probably means that they didn't actually do anything useful,
and I was just seeing the same intermittence of symptoms as before I'd
tried anything.

Initial scan of Internet sales sites seems to indicate that a replacement
keyboard is something like $50 (plus shipping time/cost; BTW, this is the
wrong keyboard, but the best [most hilarious] discount I've seen in a while:
<http://amzn.com/B00DDVJZTK> "List price: $1,702.13; Price: $51.22;
You Save: $1,650.91 (97%)". I guess the translation is "a lot cheaper
than buying a whole new laptop").

> If you want to clean it I'd recommend removing the keyboard and using
> rubbing alcohol or distilled water. I get a box of alcohol pads from
> CVS and it's very convenient for occasional cleaning.

The other thought I had was maybe one of the "DeoxIT" products.
I've never used any of them, though; and I've got a knowledge-hole
in just the right spot to make me worry, if there is actually
something amiss *inside the keyboard* that might be solved by cleaning,
if feeding anything _into it_ the keyboard might, say, un-do whatever glue
is holding the little carbon conductors onto the undersides of the rubber domes
and just accelerate me to the `try buying a new keyboard' stage.

One of the things that surprised me, when I removed the keyboard,
is that contacts on the end of the ribbon cable are *black* rather
than being either silver or gold in color as I was expecting.
Looking at it through a loupe, it looks like there's actually
a thin sheet of carbon or similar-looking material installed
as a layer over the contacts. Made me hesitate before trying
the alcohol swab; actually, it makes me wonder whether those
contacts are really cleanable at all.

> Joshua Judson Rosen wrote:
>
>> I've got this weird problem with the keyboard on my laptop: I've got
>> a bunch of keys that intermittently become dependent on some other keys.
>> 
>> Every so often, the Y, U, J, 9, comma, Enter, and Home keys all stop working
>> unless I hold down either W or left Shift or Caps Lock. Then they actually
>> trigger (though not in a way that's useful since I'm holding down other keys
>> that prevents software from interpreting them in the normal way...).
>> 
>> I gather that the Y, U, J, 9, comma, Enter, and Home keys are all sharing
>> a signal line or something, which would explain why they all go out together;
>> how holding other keys effectively routes around that damage..., I'm clueless.
>> 
>> But I think my question is: how likely is this to be caused by some sort of debris or
>> corrosion somewhere (under one of the keys? on the contacts on the ribbon-cable?),
>> and, if so, what would be the right (non-destructive) way of clearing it out?
>> 
>> This can't possibly be a software issue, right?
>> 
>> Anyone dealt with anything like this before?
>> 




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