Water spill and T420 doesn't boot

[halpulaar]

Hey guys,
I spilled water on my keyboard and immediately turned laptop upside down to avoid water going in, switched off and removed battery.
Initially, I managed to start the laptop (Ubuntu) and after login in, I could not use the mouse. I restarted again and now, it won't boot. when I start the t420, the screen lights up slightly and the bluetooth light is on. Nothing else happens from then on despite leaving it overnight. I can hear the fan and disk turning when listening closer to the laptop. I removed the disk (Ubuntu OS) to read externally with a Windows laptop but no data accessible there. I assume Windows cannot read it. I also swapped the memory cards to check but no change. One memory card is under the keyboard, the other one at the back of the laptop. I returned all in their original place (disk and memory cards).

Question is : what is wrong on the laptop, do I need to change the motherboard ? please suggest video link then. or do I need to change something else ?
I am stuck and suspect the system board might be affected. Given how difficult it is to access the system board, I thought I will ask on here some advice before buying one and trying to change. I never disassembled a laptop before and looked at some online videos. Looks like it is all about unscrewing here and there. Or is it more complicated ?

Any advice on potential issue welcome.

[Neil]

Give it several days, a week even, to fully dry out, then try again. It takes much longer than you think for the tiny amount of moisture to dry up, that can cause a short circuit. If it still doesn't work then, I would try a replacement keyboard first, then the system board.

[MikalE]

Attempting to boot the machine before allowing it to thoroughly dry probably did more damage than the initial spill.

Open up the machine's access panels, remove the memory, keyboard, any drives, and let air dry for a week or more.

[halpulaar]

Thanks MikalE and Neil. I wish I knew before trying to restart desperately and several times...
Will leave to dry and see what happens in a week or two. Shall update this thread afterwards

[mikemex]

It surely takes ages to dry up. I have a fuzzy memory about spilling liquid over something (don't remember what exactly) and checking it after two or three weeks it still had traces of it.

Heck, my X301 still has alcohol in the refractive sheets that got sucked in by capillarity when I was cleaning it. It seems like it's going to stay there until the end of the world.

[wsalomon]

Hopefully it's dried up by now.

But other possibilities are:
1 . Put it in a plastic bag with Silica Gel desiccant (look on E-bay for it) in warm place.
2. Try putting it in the freezer with the keyboard off and if water is in there, it will freeze and then sublime (go from frozen to gaseous state) if in an area where the freezer blower is active.

And if worse comes to worst, the Hardware Maintenance Manual is superb for replacing the mother board with a small Philips screwdriver, thermal paste (Arctic Silver 5), and isopropyl alcohol (or Arctic Clean) for the CPU/GPU and heatsink.

Be thankful it didn't to what happen to a friend where the water (Gin & Tonic) got through the keyboard to the WiFi card, shorted it, and melted part of the motherboard WiFi socket. It will have "phenolic-stink" forever, even with a new motherboard. The crystalized Tonic sugar was a dead give-away...