Saving an Apple USB keyboard
As usual, I cannot be responsible for any damage to
your machines when you will experiment the following
Update of the 6 June 2004
This keyboard was attacked by a grape fruit juice ;-)
This saving operation can also be done if the keyboard
received coke or coffee!
But if the electrical contacts have been oxidized too
much or if the electronic circuits have to be repared, the
operation is not profitable
Unplug the keyboard. Note that, the quicker we operate
the patient, the more providential will be the surgery!
Very dirty..on the foundation (white arrow), between keys
(yellow arrow)... and several keys are glued (blue arrows)!
Viewing the keyboard from this angle, we can not imagine
it is so dirty.
Rear view. Yellow arrows point to classical cruciform
Blue ones point to cruciform screws with washers.
White arrows show screws on the other face.
As on the pro keyboard, one screw lies behind the CAPS
lock key (yellow arrow). This key has been removed whith a
lever: we slightly lift it up.
The blue arrow points to the LED. Please, do not loose
The two screws removed: the one on the USB connector side
is bigger and has as separate washer.
Once the 4 screws removed, we have to unhook the upper
See the clamps pointed by the yellow arrows.
A zoom on one of them.
More difficult: clamps on the user face... one under the
It is advisory to remove the keyboard's keys which hide
As the yellow arrow shows it, thera are lugs which
sideways fix the clamp :-(
The removed clamp.
-> we see this when we succeed.
The yellow arrow shows an clamp for which we succeed...
the blue ones, clamps for which we failed :-(
Th second screw which locks the keyboard on its
foundation (the first screw is under the CAPS lock key).
To clean such a dirty keyboard, we have to use the
unkook all the keys!
Warning: the longest ones (space bar,... ) have metallic
clamps/glides -> unhook them smoothly!
The nude keyboard.
As on the pro
keyboard, two screws fix the USB cable's protection. The
blue arrow points to the ground screw we also have to
On the right, some residue of a sticker which is supposed
to hide the "technical" aspect of the stuff ;-)
The yellow arrow points to the part which clamps the USB
cable and which also have to be removed.
We have to unhook the USB connector to avoid damaging the
... On both sides, of course.
We can see the grape fruit juice attack!
We unhook the metallic part and deeply clean all!
We can upturn the keyboard which we extract from its
On the left, one of the lug which help us to put in place
the three films building the keyboard.
Grape juice is everywhere! All must be cleaned:
there (yellow arrows) to avoid oxidation and damage of
the cables girdles...
... and there (blue arrow) to have all the components clean!
Then, we can unscrew the card and related electronic
We can see that juice has spread out (yellow and blue
We can also see contact between films (uppest white
arrow) and the card below (lowest white arrow).
We clean both areas with isopropyllic alcohol.
Yellow arrows show the contacts to be cleaned.
The blue arrow points to a screw. All of them have to be
removed and place in a secure place to avoid to loose them!
All the screws removed, we can separate the lower part of
the keyboard... which is in in fact in the foreground in
Delicacy and precision are required!
When removing the metallic foundation and the films, we
free the silicone cells: big ones (blue arrow), small green
ones (white arrow)... well... small ones are not always
Yellow arrows show grape juice deposits.
The first film removed, we find the insulating film and
the last third one.
The 3 separetd layers: the two ones which contain the
electronic circuits are pointed by the yellow arrows, the
blue arrow points to the insulating one.
Now, we can check the electronic circuits.
The yellow arrow points to a fully oxidized contact.
The two blue ones show less oxidized contacts... but they
also are electrically out :-(
To be sure to clean all... without loosing pieces... we
have to removed all the silicone cells and the dark plastic
The yellow arrow shows the LED: avoid to loose it,
otherwise you will have no way to see the state of the CAPS
The keys support..nude! It can be therefore deeply
... like this.
Back to the electronic circuits. I scratch off all the
the oxidized parts dirts but I also removed a part of the
plastic girdle on the still conducting part of the circuit.
Then, I redraw the circuit using a special conducting
I had to put 3 layers of painting to be sure of the
circuit. Between each of them, allow 1 day for drying.
-> if I count the time I spend on this keyboard + the
20 euros of the special painting, this operation is not, in
my opinion, financially profitable.
Elisabeth emailed me that, in place of
the painting, she used a special pen:
(or web-search with" conducting pen" )
Standard : ref 823084 - 28,35 euros (Elisabeth used this
one... and only one layer)
Micro one : ref 823070 - 28,50 euros
A newly reconstructed contact.
When all layers of painting are in their drying process,
we can do all the remaining things: cleaning the keys,
checking the circuits.
To do this, we have to unweld the plate we see above.
I prefer to work with an unwelding pump (note of the
traductor: cannot find any other word to translate this
specialized tool for removibg welds).
There are 4 clamps.
-> you need a good unwelding pump. To test it, release
the spring with the end of the pump against the thumb. If
the pump does not stay sticked to your thumb, it is not
So now: heat the weld, bring some fresh weld and aspirate
the whole stuff.
Do not heat too much to avoid damaging the electronic
When the circuit is visible, we can see the oxidized
Really disgusting. Please pay attention to components'
Once everything is cleaned, we can follow the
instructions in a reverse order to rebuild the keyboard. The
most difficult step is to be sure that the silicone cells
are well in place.
To put back in place the keys with a metallic support, we
must first slide them in their glides.
And then push them in their location.
If you wish to thank or forsten me...