Water on upper screen

@alvinabella if you got water on it or in it, you will have to treat it like any other water ommersed device.

For now you want to stop continuing to try to charge, sync or otherwise use your DSi. This potentially can make a bad situation worse.This may further damage your phone.

The next thing to do is to clean it. Disassemble your DSi using these guides DSi Repair - iFixit. Remove your motherboard. You must remove all EMI shields. If you do not remove those, you might as well not do anything. After you removed those, clean the whole board, connectors (pay particular attention to your LCD connector and cable) and all with +90% isopropyl alcohol. Follow this guide , and even so it was written for an Apple 3G iPhone, all the points are still pertinent to your device. While you clean your board, check for any obvious damage, like burned or missing components etc. All these steps are to avoid delayed failure caused by corrosion. Best thing to do, would be to clean it with an ultrasonic cleaner, but if you do not have access to one, this will at least help. Once all this is done, reassemble your console and reevaluate. Until it is cleaned, everything will only be a guess. It is possible that you have a bad LCD and replacing the display may fix it. Even with all this, water damage has only a small chance to be fully repaired, but at least you can give it a try.