Have I killed my Model M? Some keys no longer work.

[joules]

Hi,
I have an 94 Model M made by lexmark. It was bought brand new (UNUSED) about 12 months or so ago.
Anyhow, I was giving my desk a clean yesterday and thought I'd give the keyboard a wipe too.
So I wipe down the keys with a damp sponge (it wasn't soaking) and on the underside I saw it was
fairly stained so I gave that a clean as well.
The computer was not on.
6 Hours later I came back and powered on my PC and keys ZXC were dead!
24 Hours later and the keys are still dead. The action is fine.

Does anyone please have any suggestions as to what might have gone wrong (short?),
whether its serious and if theres something that can be done to fix it?
Any suggestions would be great thanks.
Joules.

[fohat.digs]

Put in a dry place and wait 48 hours. Maybe stand it on end.

Some people recommend running keyboards through a dishwasher!

You might pull the keys in that area and make sure that there is no foreign material there.

[joules]

Some people recommend running keyboards through a dishwasher!

I've heard also that would destroy a model m?
Well, I hope you're right beause I an only type on this and the rubber dome KB is total junk, but I an't believe it outlasted this model m!

[nullstring]

Let it dry and it should be fine.

I would not, however, recommend a dishwasher..

[fohat.digs]

I meant the dishwasher thing as a sick joke.

I do not think that you have killed your Model M.

Be patient.

[joules]

I'm leaving it out in the sun all day. I've ordered nut driver so in future I'll clean it properly.
Fingers crossed.

[joules]

Fail.
Its been in the sun all day.
ZXC are completely DEAD.
I can't believe it. Massively disappointed. I really didn't think a damp sponge will kill my model m.
J.

[sleepy916]

You will probably have to take it apart to see what is going on, hopefully you will find what is causing them not to work.

[joules]

Yeh its weird and I'm upset.
But in the meantime I have to move on
and this soft dome is growing on me.  )

[Reomero]

this soft dome is growing on me.  )

Blasphemy! )

[rknize]

The later models like yours actually have drainage channels to guide spillage out of slots along the bottom edge.  It's kind of unlikely that water got into the membranes from the top.  Perhaps some got in when you wiped off the underside.  It could also be some other mechanical issue, though that seems unlikely given the board's age.

I also have a 1994, bought new in 1994.  I use it daily at work and it has been through some spills and other unpleasant events.  It still works perfectly.

[h2gofast]

I had a ssk I spilled coffee on.  Was convinced it was dead when a couple of keys stopped working.  Let it sit on a heater vent for a week and then it started working.  I think any moisture can short things out but might not kill it.  Patience is your friend.

[fohat.digs]

And remember, there are several smooth plastic sheets pressed against each other.

Even a miniscule amount of water could have gotten in there by capillary action, and would take a very long time to dry.

Another benefit of the bolt-mod - take it completely apart and make every component spotlessly clean!

[absyrd]

Let it sit on a heater vent for a week and then it started working. 

This. I have saved a few electronics by using a heating or air conditioning vent. Really sucks the humidity out of everything.

[Melvang]

I had my Ipod touch sitting on the center console of my car at work one day with the windows down.  Turned out it rained.  On top of that the wild was blowing hard enough some of the rain was probably going in the driver window and out the passenger window.  Needless to say my Ipod was so drenched that when I picked it up water was pouring out of the charging port.  I promptly shut it down after a couple minutes because the touch screen didn't want to work properly.  When I got home I put the Ipod in a ziploc bag with 2 LARGE bags of silica gel.  The little packet of stuff that gets shipped in the box for new electronics and what not.  Two days later I went to fire up my Ipod and it worked flawlessly for another 2 years after that.  For reference each bag of silica gel was about the size of two 12 oz pop cans.  I came into possession of these via the United States Navy.

Melvang

[mkawa]

if the action is fine and only those keys are dead then the controller pcb is fine. that leaves the membrane. i'd go ahead and let it dry for a bit longer (it can take a looong time for water to escape from a captive assembly) and then try again

[h2gofast]

I don't know how long it really took because I was too afraid to check it, but I forgot it was there until the wife was about to throw it out after three months.

[joules]

keys ZXC are still dead. When I have time I'll open it up.

[joules]

Sorry to bump my thread, just trying to get this fixed 

Nut driver arrived today (its cool "EDS" came with stickers  ) and I opened it up.

This thing is clean inside, theres one plastic rivet thats popped off, but thats it.
Looking at how its constructed for myself I'm even more skeptical that any water or
moisture ended up near the membrane, particularly around these keys (ZXC).

You could pour water directly over the keys it it would just drain right out.

Like I've mentioned this was bought as a brand new KB. Came with the original foam
scaffolding, but without the box...hmmm

I really want to avoid getting to the membrane and doing a whole "bolt mod".

I had a look over the controller PCB and there is only one spot where a solder stuck out.
It doesn't look right, but I'm no expert.

It sits low in the board. Looks oxidized. I haven't got a magnifying class, but what I can see is that it doesn't
appear to be making proper contact with the circuit - If at all.

Looks like a bad solder or is this normal?
I have no idea, anything is possible I guess.
Any suggestions? (I have a soldering iron)

[mich]

I'd start with connecting the membranes back and checking if it works now.

[joules]

Fail.
Tested with some aluminum tape.

@mich
Done it twice now. Everything works except those @#$% keys.

I really want to avoid cracking it open. I'd rather do some soldering that remove all those rivets.

Cool nut driver eh? Anodized Aluminum..YEH cooool. 

Going to bed now. 

[mich]

This solder point doesn't look like it has anything to do with key scanning.

BTW, did you try removing these keys and pressing directly on the hammers with a screwdriver or something?

[joules]

Let me see...

Still no.
Weird.
So the general idea is this will come good in time?
Its in pristine condition.
I'd hate to wreck it with a bolt mod for no reason, but until I get to the membrane
I can't rule out a fault there. I'll put it away for week.
Thanks for helping.

[1391406]

If worst comes to worst, you can always send it to Unicomp. They'll repair it for a nominal ($35) fee, but then for what they charge you could probably find another one on eBay.

[joules]

Unicomp is out of the question (I live in .au). Anyhow what are they going to do?
This was bought brand new, not second hand. I'm the first owner.
Chances of finding anything similar on ebay.com.au is extremely slim.
Thanks anyway

[1391406]

Unicomp is out of the question (I live in .au). Anyhow what are they going to do?

Repair it by replacing malfunctioning or broken parts.

This was bought brand new, not second hand. I'm the first owner.
Chances of finding anything similar on ebay.com.au is extremely slim.

There are Model M's on eBay.co.au. Granted, they're not new, but what good is your "new" Model M if you can't use it?

[rknize]

Looking at the matrix, it is not obvious to me why z, x, and c alone are affected.  They are in different columns and there are other keys in that row that apparently work.  Have you remove those keycaps and tried to manually actuate the membrane on those?

If we stay on the path of water intrusion, try putting the exposed plate assembly in a sunny window for a week or two.