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I have near 5 keyboards broken because poured water or juice, etc... Most problems are keys that don't work or swapped keys.

I want to know (just for electronics exercise - I know that keyboards are cheap) if it can be fixed or tested with basic electronics tools, and how I do it?

tyblu
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Click Ok
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  • Do the switches use rubber domes, or is it a quality keyboard with mechanical switches? Open it up, and post a picture. – Kevin Vermeer Dec 16 '10 at 17:30

4 Answers4

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You could try putting them through the dishwasher :)

Quoting a quote (sic) from that site:

I can report that not only will the keyboard come out clean, but it will probably work once it dries completely. Every key on the keyboard works and feels just right - the Caps Lock light even works! This ‘hack’ is not for the weakhearted, and I would probably avoid putting a $100+ keyboard in the dishwasher. But if you don’t have any other options, it’s a pretty good bet

Edit: The dishwasher fix basically just cleans out the mechanism (be it mechanical switches or diaphragm) and is a good fix for 'sticky' keys. This may work for your orange juice problem, if the sugary residue is stopping the key presses from working. Hand cleaning would also be of help here if you disassemble the keyboard. The trick is to make sure it is completely dry before plugging it back in. I'd suggest to wait a week or so after washing.

If a keyboard died due to spilled water, then most likely it caused an electrical short and damaged something on the circuit board. This doesn't mean that it is impossible to fix - standard fault finding applies, and you'll need some tools for the job (multimeter, oscilloscope come to mind).

Peter Gibson
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    nice, If I have a dishwasher... :( – Click Ok Dec 16 '10 at 04:47
  • +1 for dishwasher! After cleaning, it may be necessary to lubricate keys since sometimes lubricant can be removed by the dishwasher. – AndrejaKo Dec 16 '10 at 09:49
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    Dishwasher ist good, but: Take the keyboard apart, rinse everything that has electrical contacts with alcohol, and put only the plastic parts (top w/ keys and bottom) in the dishwasher. The detergent in the dishwasher is quite aggressive and may eat the conducting traces and contacts underneath the keys and corrode all the other contacts. – zebonaut Dec 16 '10 at 11:48
  • Take a picture of it first so you remember where the keys go? :D – endolith Dec 16 '10 at 15:23
  • This sounds like a cool idea, when I was at high school the IT technicians used to clean all the cola and gunk off the keyboards with a bucket of warm water and washing up detergent (dunk and soak), they then put them out to dry on the radiators. Personally I'd use the contact cleaner/rubbing alcohol method first, I've done this on my macbook pro three times now, for some reason the girlfriend keeps knocking whole pint glasses of juice on it ;( – Jim Dec 16 '10 at 17:01
  • @Jim - Note: not recommended for keyboards still attached to laptops :) – Peter Gibson Dec 17 '10 at 00:16
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Inexpensive keyboards are usually made with an elastomeric ("rubber") membrane that sits over a large printed circuit board. When you press a button, the plastic key collapses the dome, whose bottom has a conductive pad that can short contacts on the PCB.

If keys are not responding, it may simply be due to fouling of the pad/contact, so disassembling and cleaning should fix the problem. Clean up as much bulk residue as you can on the PCB with water, then do a final clean with alcohol. The elastomeric membrane you should be able to immerse to clean, but a final clean with alcohol may be prudent on the bottoms of the domes.

Keys being confused with one-another may indicate some additional damage to the logic, parts may be damaged irreparably, or the juice residue may simply be shorting some high impedance pins, causing confusion. A good first step would be to clean it in any case.

Nick T
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  • alcohol will also help get some of the water out places it likes to stick. basically, the alcohol just displaces the water, and the little bits of alcohol left in the nooks and crannies will evaporate much more quickly than water would. – JustJeff Feb 09 '11 at 12:47
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I really like Microsoft natural 4000 keyboard which are not cheap, and surely I pour liquids on it from time to time, and it's worth try fixing. Here are the results:

1) Clean damaged areas to remove parasitic conduction layer 2) Redraw damaged tracks using conductive glue. Also, you may plant tiny copper wires along damaged tracks to reduce resistence of glue if needed.

Success ratio 80%, some KBDs were fixed several times :-)

TFD
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BarsMonster
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    great idea with the conductive glue. I tried to fly wires once on my MS 4000 and melted the mylar layer. :) – Dave Dec 16 '10 at 14:09
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Disassemble case, rinse with warm water, then dry it in a warm place. Repeat if keys are still stuck.

At least that's what I did after I spilled a glass of white wine into a keyboard 15 years ago. After the first cleaning the down arrow key was still sticking sometimes. After the second cleaning it worked perfectly again.

starblue
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