this post was submitted on 05 Nov 2024
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Questions about water inside tablet (lemmy.world)
submitted 2 days ago* (last edited 2 days ago) by [email protected] to c/[email protected]
13 comments fedilink hide all child comments
 

So I accidentally put an open water bottle in my bag while my tablet was in there, LCD was unfortunately flooded, but I ordered a replacement screen and it arrived today. Though opening up the tablet I found water droplets throughout, so I removed every part meticulously to put in rice or something and noted any current corrosion I had to remove with a q tip.

My question is this. As soon as I opened it up I noticed the water very quickly evaporating. I actually can't see any more now. Anyone who does mobile device repairs, what do you think? Could I skip the deep-dry? I looked at all the components and none of them have any parts that could have trapped water that I missed and I don't really look forward to cleaning the entire thing of starch ( though I do just have silica beads but let's stay on topic)

Am I right to feel confident about the dryness of the components? Let me know!

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[–] [email protected] 1 points 1 day ago

You’ve already got answers about rice so I won’t comment on that.

Once you’ve noted the corroded places, clean it by using 99% isopropyl alcohol and an ESD brush. In lieu of an ESD brush, a regular toothbrush is usually fine but best practice is to adhere to ESD protocols.

The main area you won’t be able to get to is the BGA underneath some of the ICs. To clean under there, the board would need to be put through an ultrasonic cleaner.

I usually give any wet board 24 hours to dry with a fan circulating air over it, flipping the board around the 12 hour mark. Humidity is usually 30-60% where I live.

[–] [email protected] 11 points 2 days ago (1 children)

Don't put any rice near it. Use the silica bags.

[–] [email protected] 1 points 2 days ago (1 children)

Alright, and what about the not seeing any moisture?

[–] [email protected] 4 points 2 days ago (1 children)

You can't see under the chips, my guy. Put it in a warm place or with silica bags as suggested and let it dry for safety.

[–] [email protected] 3 points 2 days ago* (last edited 2 days ago)

Alright I won't take the risk then, I'll take a look at it with the video microscope to look for corrosion then toss the components in a silica bag

[–] [email protected] 4 points 2 days ago (1 children)

You ordered a replacement screen and wait for it to arrive before even opening the device? Why?

Removing corrosion means it will be harder to see where the damage is.

Next time:

  1. Open as soon as ASAP possible!
  2. Disconnect battery.
  3. Let it dry. No rice or dog shit or whatever. Proper desiccant or nothing.
  4. Reconnect battery and test.
  5. Win or start debugging.
  6. Fix it
  7. Remove corrosion when everything works only now - unless you expect it to cause the issue, then at least document it before cleaning.
[–] [email protected] 1 points 2 days ago (1 children)

Making a few assumptions here,

  1. I hadn't thought about it, but the device worked and the screen clearly had liquid trapped between the layers. So once I saw that I turned it off, and ordered a new screen, because believe it or not, desiccant doesn't do jack for a waterlogged LCD.

  2. I said "noted" corrosion, not that I went ahead and removed it

[–] [email protected] 3 points 1 day ago (1 children)

So the Qtip part did not happen? Ok.

[–] [email protected] 3 points 1 day ago (1 children)

No that's gonna be after drying, I also have this really fancy HD microscope I use for solder but I'll be checking out each component I can looking for damages

[–] [email protected] 2 points 1 day ago

Perfect.

[–] [email protected] 3 points 2 days ago

The motherboard can be cleaned with a generous amount of isopropyl alcohol. It cleans slightly corroded areas, displaces water, is not a good conductor of electricity and evaporates easily.

[–] [email protected] 3 points 2 days ago* (last edited 2 days ago) (1 children)

Rice is bad because it doesnt actually absorb much moisture and can cause mold growth

Better to put it in front of a fan to add air circulation and maybe warm it a bit (i.e. near ish to a heater but not on it)

[–] [email protected] 1 points 2 days ago

I didn't know this, thank you for the info