This is perhaps my second most favorite kind of repair (after data recovery).
The owner, I felt, had pretty much accepted this laptop’s demise after it had sufferered a leaky ceiling driping water onto it. It had functioned stoically for a further two months before becoming completely unresponsive, no screen, no charging lights, etc.
Water had sat contained in the plastic chasis and over time corroded the I/O board and its ribbon cable. This eventually caused a short on the BIOS battery and the main battery reducing both to absolutely nothing.
Fortunately, spares were available and so cleaning was not necessary.
The moral of this story…
Liquid damage doesn’t always kill laptops immediately!
If you get liquid in your laptops and gadgets, even if they still work, the best course of action is to get it looked at and dried out as soon as you can.