Any chance to recover Bangle.js 2 that got wet?

Hi. I totally forgot that I'm wearing a non-waterproof Bangle.js 2 and swam in a very salty sea. After a while I noticed that the watch display doesn't show anything. Maybe it turned off, maybe the display died, I don't know. After two weeks it still doesn't work - display show nothing, pressing the button or charging doesn't help. Is there any chance in trying to open it and find and clean/replace some faulty component or should I think about getting a new one?

Argh, sorry to hear that. After 2 weeks you'd have hoped it would have dried out a bit, and if it still doesn't work it's not great news.

But in a way you don't have much to lose and there is a reasonable chance it could be recovered. There's a post here where someone gives instructions for dismantling their Bangle 2: http://forum.espruino.com/conversations/373434/#comment16672619

Once you have the screen off, take the PCB out and submerge it in totally clear water. If there's corrosion go at it with a toothbrush. Leave it it more fresh water (in case there's still salt under some chips) then leave it to dry somewhere warm for a few days...

And maybe that'll fix it - if there's no serious corrosion visible then I think you have a pretty good chance.

Thank you for an inspiring advice, will definitely try it!

So I've finally found time to disassemble the watch. I can see some corrosion (attached the pictures). Is it considered much? Should I still try to soak it in water and dry it? If I soak it, should I remove the battery somehow? How is the battery removed? Also, I think I overheated the display. Ignore the sticky spot on the display, it's just some glue from the "tool" that I've used to remove it, but the blueish spot concerns me.

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Hi,

Well, the corrosion doesn't look great (I wonder what's underneath the metal shield that covers the GPS) but actually there doesn't seem to be much corrosion under the microcontroller and it seems like there's a good chance the corrosion under the crystals (the two small silver rectangles) is what was stopping it from working.

So yes, I'd soak it - maybe just hold it under a tap and give that whole area by the aerial a really good scrub with a toothbrush or something. The battery is held on with double-sided tape (and the vibration motor in the middle is held to the battery by tape) - but personally I wouldn't bother removing them - ideally the bit of the battery with the yellow tape on it wouldn't get wet, but the rest of it is basically sealed.

I'm afraid the display does look like to could be broken though, and it's not something I have any spares of. Did the color change back to be constant after it cooled? Or is that the way it looks now?

So... Now you're this far I'd give it a go and see if it works, but the display may not work properly all over after :(

Hi,

The display now constantly looks like that. I don't think there's a chance that the display will work, or is there?

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I think it's likely the display will work and be visible in the area that's dark, but probably the rest won't be visible.

It might be worth leaving it for a bit just in case it recovers a little over time, but I don't hold out much hope.

I'm afraid the LCDs are just really sensitive to temperature. You need to be super careful not to get them anywhere above 100 (I've broken one or two myself, exact the same as yours).

Got it. So I'll just try to rinse the circuitry as you've adviced just out of curiosity. 🙂 Huge thanks for the responses!

I guess it's bad news. I rinsed the board and connectors with tap water and brushed them with a toothbrush, dried it with an electric heater, put it all together, attached the charger, waited for a couple of minutes, tried pressing the button several times, but no signs of life in this watch... Since the display and insulation around it are already ruined anyway, I think I'll just invest in a new bangle and take better care of my stuff in the future. This is a good lesson for me.

I've just tried to attach the charger again after 12 hours and it displayed several lines of text at the bottom of the screen for a moment, but then the text disappeared and it doesn't show any signs of life again. Tried reattaching the charger, pressing the button, but nothing.

EDIT: OMG! It works! Long pressing the button helped! And the whole display works!

EDIT: So after I've found that it's working, I've been testing several functions/sensors to assess the damage.
The thermometer app says it's -136°C and the barometer says it's 741 (something), so I suppose it's not working correctly.
The compass kinda works, although it's like 20° off compared to my phone which I believe is really accurate, and if I move the watch up or down then the measurement gets way off and doesn't come back to normal unless I restart the app, and the arrow is constantly jumping in a range of like 15°. I'm not sure whether it's the app or maybe it's normal for this sensor.
The GPS app says it's using 0 satellites and is waiting for GPS, even when I'm out in an open area, so I believe it's completely dead.
However, I can't be sure about anything I've found to be not working as I haven't tested those apps before I submerged my watch into the sea. I would love someone to do very short tests, just download the Thermometer, Barometer, Compass and GPS Info apps and post here what they're telling. That would be of a very very huge value to me.

EDIT: After a day of usage I've also noticed that the battery is draining much faster. Does this indicate that something is shorting?

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Well, that's better than we thought I guess! The circuitry can take quite a while to dry off though - under chips and especially in that 'tin can' a few minutes under hot air may not be enough to fix it.

The thermometer/barometer are the same chip, and might clear up after a while I guess. IIRC the barometer's normal value is around 1000 (when near sea level) so 700 may not be too far off.

The LCD seems usable at least - I wonder if you changed the theme to black on white it may not look so bad?

I've also noticed that the battery is draining much faster. Does this indicate that something is shorting?

Yes - it could be a sign the PCB isn't yet fully dry, but it could also be that there is still salt between some tracks. If you wanted to go further it might be worth desoldering the metal 'tin can' and seeing what's under there (no need to put it back really - although it may help with GPS sensitivity) as it could be corrosion around the GPS chip that is causing the increased power draw.

The display is absolutely usable and it's the least of all the problems. The biggest problem for me is the battery drain. It took only three days for it to completely discharge in stand by mode. Currently I don't feel like going so hardcore like desoldering, etc. I'm more into IoT software nowadays, and Espruino - especially the Bangle - seems awesome for this case.