Need help troubleshooting an inoperable display damaged by water

Whenever a liquid spill occurs the first thing that has to happen is the laptop should be shut down immediately. All power must be removed as soon as possible. It is especially important that the battery be disconnected and removed.

All affected parts must be removed from the laptop. No attempt should be made to start/restart the computer since this could potentially damage the logic board beyond all repair.

Then all affected parts would be washed in deionized water and blown dry with compressed air. (In a water spill the deionized water is probably not as critical. Depends on the mineral content of the water.).

This is especially true of the large chips on the logic board. Liquid can wick under them and cause havoc for weeks if not months after the incident.

The logic board should be placed in a drying/dehumidifing oven for at least two days. Longer depending on the spill.

The keyboard is a separate matter.

" It's been on the shelf for years"

Was the battery left connected all this time? If so there would be major corrosion. Most likely candidate would be the LVDS connector on the logic board. If it's severely corroded it will be irreparably damaged.

"by the time I returned from my vacation, all the water had evaporated but I could tell where it had landed and dried up."

So that's evidence that you can easily see from the outside. Once the water is inside on the logic board it wicks itself between the sub millimeter spaces between component chips and their attachments to the logic board.

Here's the GPU on a logic board that was in a water spill.

So you can see the corrosion on the large chip in the center of the image. The corrosion is white and blue/green. (Compounds of copper). The stuff on the top is not so bad as most of it is under the heat sink. The worst stuff is the evidence between the chip and the logic board itself. This would point to corrosion on the hundreds of attachments under the chip.

Here's a more extreme example. This one was in a rainstorm in Thailand. Oddly enough I was able to save the second one but the first one is still dead!

So when you're inspecting your logic board look for green and blue corrosion, especially in the LVDS connector (Video connection to the LCD.)