'TWEAKING' A FAULTY LAPTOP KEYBOARD
June 3, 2007
by Michel & Jane DeRidder

We got fed up with our Dell keyboards going on the fritz. We have replaced the keyboard three times on our eight-year-old Dell Inspiron 3700 in the four or so years that we have had it, and the previous owner also replaced a few. Fortunately EBay provides opportunities to get hold of new and used ones. It was always the most-used keys that either ceased to function entirely, or far more often, began making double letters, beginning with the a and e, then progressing to r, h, s and l. The spell check could clean up much of the resulting gobbledy-gook, but not the double, then triple spaces. We brought out the 747-like consul keyboard passed on to us by concerned buddies, or just coped with the faulty keyboard.

The 747-like consul keyboard that we sometimes used when the going got too tough.

Then, one fine day we unearthed an early keyboard given to us by our computer guru friend whose laptop it was. Michel took it apart layer by layer, thankful that we never throw things away, just in case they might come in handy one day. He decided to find out how the thing works, and perhaps how it might be repaired. Time is plentiful on Magic Dragon, and patience for such puzzles seemingly endless. He spent hours studying the action of the keys and tracing the circuitry, noticing that where the control fingers habitually touch the electronic printed circuit, there were wear spots.

The wizard studying the innards of a keyboard.

Magic Dragon's resident electronics technician came to the conclusion that if he were to tweak the metal contact finger sideways on the underside of each malfunctioning key and also give it a bit of extra "spring", that just might help. So with nothing to lose and much to gain, he did just that, but on troublesome keys only. Lo and behold! It worked. We celebrated with a spate of emails, quickly done for a change. Michel took a macro picture of the mechanism showing how he bent a metal "finger" sideways in order to demonstrate what is involved should anyone else choose to repair a Dell keyboard instead of replacing it (or instead of deep-sixing the entire laptop in a fit of pique, something we understand sometimes does happen).

The tweaked key contact finger that solved the problem.

Another keyboard failure that Michel has managed to overcome in the past is the one where a whole diagonal row of keys gives out. This is a contact problem, he discovered, caused by corrosion, one brought about by unwashed salty hands, we suspect. Usually by cleaning the contacts of the harness where it plugs in, he could resurrect the dead row of letters. Once he scraped off some of the gold contact in his over-enthusiasm. In that instance, he carefully cut a fraction of an inch off the harness, and reinserted it. It worked thereafter.

For simpler corrosion problems, a sun bath has helped short term, as we have mentioned several time before. Best to remove the computer battery first, I suspect.

Post Script

Just three weeks to the day after the miracle "cure", the Dell reverted to some of its old tricks - the occasional double letter, including the "A", which had been operated on, but also the "W", which had not. I can understand the W begging for attention, but not the A which had been tweaked. Back to the drawing board.

This time rather than looking for keyboards on EBay, I found a Singapore computer parts outfit on the net called PCHub.com. They have new keyboards galore in stock! I ordered two so as to have a spare, since they are selling for only USD $12 each and shipping was $17, same for one or two boards.

Inside of a week the package was in our mail box. Marvellous new keyboards in sealed wrappings. The one installed works just fine, no double letters anymore. The only problem is that my guess of board model number between half a dozen or more for this laptop was not the right guess...18 of the keys have different key cap labels to confuse us! Must be a keyboard for Portuguese or something like that and ? / = etc are on different keys beside offering accented vowels on some keys...Live and learn. PCHub seems to be an efficient outfit and they have been very prompt at answering my emails as well as sending out the order. We now are trying to locate Key decals for the Dell keyboard.